Lilah Morgan was a true Magnificent Bastard, but eventually she had to die and be replaced, and that replacement was Eve. As Poor Man's Substitute for Lilah, Eve inevitably came off as a Smug Snake, but the writers seemed to realize this, and put her through a series of events that had the effect of breaking the cutie.
Lilah herself only slowly evolved into a Magnificent Bastard; earlier in the show she was definitely a Smug Snake, even ending up with a promotion - and thus her life - solely because Lindsey contemptuously tossed it away.
The true Smug Snake in Angel was Gavin Park. Gavin believed himself to be the next Lindsey McDonald, a Magnificent Bastard who could arguably be called Angel's Archenemy (well, he would argue that he could), but he just wasn't the man, lawyer or villain that he'd replaced.
The A-Team: Pick any villain from any episode, any villain.
G'Kar during the first season and especially in the pilot movie.
Also, Mister Morden, with his ever annoying arrogant smile. J. Michael Straczynski points out in the commentary that he specifically loved the actor for how unlikeably smug he made the character come off: "Look at that guy! Don't you just want to hate him?"
Captain Kevin Darling, a snotty little creep who, working safely behind the battlelines as General Melchett's adjutant officer, has made it his life's mission to make sure that Blackadder doesn't escape the trenches of World War One. He's loathed by Blackadder for obvious reasons; however, despite (or because of) all his sucking up, the General can't stand him either, at one point informing Darling that he regards him as a son - just not a particularly well-liked one.
To say nothing of The Black Adder himself, Prince "Sniveling Worm" Edmund, Duke of Edinburgh, who thinks himself quite the Magnificent Bastard, while his contemporaries regard him with a mixture of pity and contempt. His various throne-usurping schemes either fail spectacularly, end up biting him in the ass, or both. Thankfully, his descendants gained several layers of Magnificent Bastardry, presumably from their (unseen) matriarch.
Breaking Bad: Several characters, but sleazy cartel boss Don Eladio and Todd, the child-killing Neo-Nazi thug are two standout examples. In the 5th season, Walt himself also edges dangerously close to this territory, particularly in his interactions with Skyler.
There's also the cartel capo, Juan Bolsa, who clearly thinks he is far smarter than GustavoFring. Simply put, he is not and is proven wrong in a spectacular fashion.
Glory is not even a tenth as smart or diabolical as she thinks she is. If it weren't for her immense physical abilities and tendency to go off half-cocked, the gang probably could have outsmarted her without breaking a sweat.
Warren brags to anyone who will listen when he thinks he has killed Buffy. The vampires around him are only too happy to wipe the smug grin off his face when they tell that not only will Buffy be alive and well very soon but he just killed one of her friends and pissed her off.
Camelot: In this Starz TV series, Merlin comes across as a condescending, ill-tempered and unpleasant character, in contrast to his lovably Adorkable counterpart in Merlin. The Sword in the Stone was just a ruse staged by him to trick the people of Camelot into accepting Arthur as their king. Merlin has a Yandere-like obsession with Arthur, believing him to be the indisputable ruler of the land, even though this Arthur is portrayed as a whiny, self-centeredJerkass. Merlin has nothing but contempt for the people of Britain, describing them as "a chorus of fools". His nemesis, Lady Morgan, on the other hand is a thoroughly Magnificent Bitch, and at one point he ends up being towed behind her carriage with a rope around his wrists, resulting in a Crowning Moment of Funny.
Chuck: Villainous CIA representative Clyde Decker is always seen with a smug grin and frequently talks about a big plan meant to take down Chuck and his allies. However, it turns out that Decker himself is just a pawn in a larger plan by Daniel Shaw to bring down Chuck, as we find out "Chuck Versus the Santa Suit".
Criminal Minds: Being a show about Serial Killers more than a few of the villains are like this, especially those that suffer from Antisocial Personality Disorder or Narcissistic Personality Disorder. George Foyet, The Boston Reaper, is one of the best examples, being a sociopath who suffers from Lack of Empathy, It's All About Me, and an ego the size of a blimp. He takes offense at the idea that anyone would dare to try and stop him, torments Hotch for no better reason than his incredibly petty ideas of Revenge by Proxy, is killing people for the fame more than anything else, and takes such a sadistic delight in everything he does that it's impossible to admire him, despite his undeniable genius. The poster boy for this trope, however, is probably the Season 2 Final Boss, Frank Breitkopf. While he has more sympathetic qualities than The Reaper, Keith Carradine plays him with such slimy arrogance that it's impossible to like him, or even admire him. He comes off like an evil college professor: you are going to learn something, no matter how painful it might be.
CSI: Crime Scene Investigation: Conrad Ecklie, at least for the first half or so of the show. He's The Rival to Grissom and is only in the law enforcement business for money and glory; in an early appearance he worked to get Nick convicted of the murder of his Hooker with a Heart of Gold girlfriend, even though the woman's pimp was a more likely suspect, just to piss Grissom off. He changes in the season 5 finale after his actions to split up Grissom's team lead to one of them being horrifically tortured.
Dark Oracle: Both Vern and Omen have severe Smug Snake tendencies, with both being arrogant, self-centered, quickly offended, and prone to wildly overestimating their own abilites. Of the two, Omen is the most serious threat, as he almost has the power to back up his bragging; both eventually Heel-Face Turn and, in Omen's case, lose most of the Smug Snakeness.
"Amy's Choice" features the unbelievably punchable Dream Lord.
In A Good Man Goes to War Madame Kovarian did manage to spectacularly outmaneuver the Doctor, but in The Wedding of River Song she is genuinely surprised to be the victim of You Have Outlived Your Usefulness from the ruthless murderers she has as allies, and then shows that Villains Want Mercy and asks Amy to save her, totally confident that she will, because despite kidnapping and brainwashing her baby, "[Amy would] never do anything to disappoint [her] precious Doctor". The Oh Crap look on her face when she realizes just what a Mama Bear Amy is when the Doctor is not actually present is very satisfying. And even if she wasn't noticeably less competent than she believes herself to be, her overall smarmy, oily demeanor would be enough to make her this trope.
Plenty of villains from the classic series, including Mavic Chen, and Soldeed, qualify — the two mentioned are both overconfident and both only think they have control over their respective Villain of the Week, when said villains are obviously playing them like harps.
Grunchlk, a bloated, scheming, greedy merchant with a nasty habit of overcharging his clients and betraying them should a better offer appear. In the episodes he appears in, every single character despises him with a passion, especially Scorpius, who takes great delight in stabbing him in the back of the skull with a Mind Control probe and forcing him to eat two of his own fingers.
Commandant Grayza; a smug, vindictive and generally repulsive Peacekeeper who wasn't nearly as smart as she thought she was, and eventually got completely owned by the Scarrans before being removed by her own lieutenant for incompetence.
Prince Clavor from the "Look At The Princess" trilogy: a whiny, posturing and thoroughly smug little bastard that wants the throne of the Royal Planet for himself- but probably wouldn't have been able to string half of his plan together without Scarran help. And he pays for it throughout the story: his mother plots to keep him off the throne, his fiance plans to assassinate him if he ever takes power, Crichton slaps him about... finally, the Scarran ambassador decides that control over the Royal Planet isn't worth another minute of Clavor's smugness, and fries the bastard alive.
Flash Forward: Uncle Teddy AKA Flosso. He's a Fat Bastard who smokes a lot, is a Card-Carrying Villain, has people killed without a qualm, thinks he's so smart, and bullies Simon. However, he gets his comeuppance when he has Simon come with him, just the two of them, reveals Simon's professor's corpse in a car trunk, and tells Simon to comply and that this is his last warning. In a Moment Of Awesome, Simon says "I'm calling your bluff! You need me too much!" The look on Flosso's face at that point was priceless. Simon shoves Flosso down to the ground and presses on his windpipe. He smokes a lot, so he suffocates rather quickly and dies.
General Hospital: Not only does Lisa Niles fit this to a T, she gets bonus points for being a total psycho. She seriously believed that killing Robin would make Patrick fall in love with her. All her attempts to off Robin failed. Most recently, Lisa fell into a coma after accidentally sticking herself with a syringe full of toxic drain cleaner that she meant to use on Robin.
Gold Rush: Dakota Fred easily qualifies, acting like a douchebag when working with the Hoffmans in the first season, then backstabbing them and buying the claim out from under them in season 2, forcing them to find another site to mine.
Season 3 Big Bad Arthur Petrelli: between his ludicrous amounts of power, constant dog-kicking and smug, smarmy tone throughout it all.
Eric Doyle, the creepy puppet-master from season 3 also qualifies. Creepy and smarmy, he's the kind of villain audiences just love to hate.
Horrible Histories: William Shakespeare is presented this way, especially in the HH Proms skits. In his case, he genuinely is a handsome, witty genius who invented plenty of beautiful new words and phrases and wrote a lot of great stories, but he also takes credit for other peoples' work if it has any similarity to anything he did (even picking on Cleopatra for telling her own story in her own way because he thinks Antony And Cleopatra is better) and is so condescending to other people that we cheer when he gets punched.
JAG: The first Secretary of the Navy (SecNav), Alexander Nelson fits this trope.
Jekyll: Benjamin. His comeuppance was most satisfying.
Kamen Rider Agito: While we're on the subject of Kamen Rider, this trope would not be complete without mention of Houjou. He spends the entire series trying to undermine the G3 crew in multiple ways, from guile-ing his way into becoming the G3 Operator, to proposing a competing powered armor system, to trying to capture Agito just to render G3 obsolete. The worst part is, every time he gets shut down, he only seems to get worse.
Kamen Rider Dragon Knight: Drew Lansing (a.k.a. Kamen Rider Torque), one of Big Bad General Xaviax's lieutenants, fancies himself both an expert manipulator and fighter. Eventually, he proves lacking in both areas.
Many, many criminal defendants from the various shows.
Some of the defense attorneys cross the line into this. Mike Cutter debateably started out as an Anti-Heroic variant.
Law & Order/Homicide: Life on the Street crossover "Sideshow" features Independent Counsel William Dell. During the course of the two-parter, he abuses his grand jury subpoena power, lies to police, commits blackmail, derails a major character's judicial appointment, cons defendants with bogus immunity agreements, sabotages a plea bargain between the Baltimore prosecutors and a key witness, and finally gives full state and federal immunity to a murderer so he can secure uncorroborated (and probably false) testimony implicating the President in his crime. When confronted at the end of the episode about his decision to torpedo a murderer investigation for political gain, he accuses McCoy and Danvers of being "petty" and "savage" in their lawyering, because "the stakes are so damn small."
Bobbi Barret, the wife and manager of comedian Jimmy Barret, ends up like this in one episode. Jimmy had previously insulted the wife of the owner of Utz potato chips, which he was doing a commercial for. Don Draper takes most of the episode negotiating with Bobbi to get him to apologize. After the two end up having sex (don't ask) Bobbi agrees to a dinnertime apology. But Jimmy spends all his time at the dinner hitting on Don's wife. When Don takes Bobbi aside, she says that according to Jimmy's contract he doesn't have to apologize, unless Don gets them more money. So Don shoves his hand up her dress and says that if he doesn't, he'll ruin Jimmy. Jimmy apologizes.
Pete Campbell is constantly this, although he does get somewhat better about it as the show goes on. He's never as bad as Roger.
Don can be this himself occasionally.
M*A*S*H: Dr. Frank Burns is this. His replacement, Dr. Maj. Charles Emerson Winchester III, is the king of this trope. If one needs proof, watch "An Eye for a Tooth", and notice the ending.
Merlin: Morgana walks around with a perpetual smirk on her face, even though every single one of her plans to kill Uther, Arthur and Merlin have completely failed. She's also apparently under the assumption that her Complexity Addiction makes her The Chessmaster. Also, the fact that Merlin knows she's actually evil and can't tell Uther means his hands are tied. It's gotten to the point where she admits, to his face, that he was singlehandedly responsible for thwarting her takeover of Camelot and killing her sister, and she still mocks him about how useless he is.
Murder One: Malcolm Dietrich in season two was a very, very obvious attempt to replicate the magic the show had with Richard Cross, the Magnificent Bastard from the first season. For whatever reason it just didn't work, though undoubtedly at least part of this was due to not being able to score as good an actor as Stanley Tucci, who had played Cross.
The Office (US): Charles Miner replaces Michael and responds to his eccentricity with realistic exasperation. However, his time in charge is largely characterized by appointing his employees with mismatched roles, bullying Jim at any chance he can get, and being all-around smug.
Oz: You could make an entire page of examples, which is to expected given its prison setting. On the inmate side of things, the absolute worst is Timmy Kirk. A self-righteous, manipulative sociopath who always wears a smirk on his face, Kirk fancies himself as a Magnificent Bastard, but lacks any of the gravitas of one, and is impossible to like. True to form, when he's brought down for his actions, he nearly breaks down in tears. On the opposite side of the law, Governor James Devlin is a typical example of a smug politician who abuses his power to do anything he likes, and exhibits the same sociopathic tendencies that many of the inmates do.
Power Rangers: Every Big Bad has at least one scheming lackey utterly convinced that they're superior to the remainder of the universe and willing to backstab anyone in their way. This usually ends with them being converted (if brainwashed into snakedom) or, much more often, exploding violently by either side's hand.
Primeval: Lester is a curious case, he starts off as an archetypal Smug Snake, but it's revealed that this is more a Jerkass Fašade than anything else, his awesome powers of Sarcasm really shine through in season 2 when he's given his own Smug Snake nemesis in his assistant and Starscream wannabe, Leek and by season 3 his return from a 10-Minute Retirement is given a Standing Ovation, and yet all the time he retains his aura of smug self-satisfaction. A rare heroic Smug Snake perhaps.
Prince Amongst Men: This is why this short-lived BBC sitcom didn't work — the title character was a Smug Snake, when he needed to be a Magnificent Bastard. Not only that, but the creators missed the point that we sympathize with, for example, Blackadder because the world really does seem out to get him and he's just fighting back. Gary Prince's world seemed to be incredibly on his side, to the point where he was a Jerk Sue.
Brad Bellick in the season 1 practically embodies this trope. As a corrupt correctional officer, he certainly acts like a Magnificent Bastard. He deals with former mob-boss Abruzzi, has a history of inmate abuse, insults T-Bag to his face and interrupts Michael's plans quite often. But at the same time, he's obnoxious, sleazy, importunate, and cowardly.
Agent Kim from season 2 is another notorious example, lording and sneering over our heroes while being generally inept in almost all of his endeavors, then getting done in by the most unlikely of culprits.
Don Self after he was revealed to be The Mole. Where Bellick had at least some sense of magnificence, this guy's just too annoying to like.
Robin Hood: The Sheriff of Nottingham of this BBC series seems to count himself a great Magnificent Bastard, but in practice his evil works tend to be rather too easily foiled by Robin Hood's men to be considered the work of a true evil genius. Furthermore, his 'la-di-da-di-da!' catchphrase, often uttered as a sign of impatient indifference in response to threats concerning the meddling of Robin Hood and his men, is much too unctuous, awkward, and obnoxious to be a distinctive of a true Magnificent Bastard.
Scrubs: While not really a villain, new med student Cole in season 9 fits the bill. Due to his wealthy family contributing tons of money to the school, Cole sees himself as "untouchable" no matter what he does, always has a smug smile on his face and a smarmy tone in his voice, and is involved in an emotionally unhealthy relationship with Lucy. Recent developments indicate he may have a decent side to him but even this might be further manipulation.
Rick Flag is a competent schemer (at least so far), but his fondness for Cold-Blooded Torture, Sociopathic Soldier status, and 1960s-ish supervillainy keep him here, especially when compared to Lex Luthor and Lionel. He's arrogant, viciously vile, and at least partially insane: he's a Badass Normal who's spent so much time around superheroes that he self-identifies as one. Lx-3 (Old!Lex), an Axe Crazy clone of Lex Luthor might count as well, as he has all of Lex's cunning and superiority, and none of his style.
Lots of one-shot villains count as well, as does Regan Matthews, a slimy Corrupt Corporate Executive who served as Lex's Dragon throughout Season 8. Arrogant, condescending and just plain unpleasant, he was nevertheless unusual for a Smug Snake as his defining trait was his Undying Loyalty to Lex.
The Vorta are a Planet of Hats of Smug Snakes, with Weyoun as the smuggest. The Jem-Hadar despise all Vorta for this, despite remaining unquestioningly loyal.
Many Cardassians are also Smug Snakes. Dukat is one, through and through while fancying himself a Magnificent Bastard. Just listening to him talk about how he feels the Bajorans should have loved him like a father while he oversaw their enslavement and the strip-mining of their world, is disgusting to the series' protagonists and highly amusing to Weyoun. Dukat even has moments where he is on the side of the heroes until he takes an opportunity to serve himself to everyone else's detriment.
Dukat's right hand and successor Damar was also a pretty Smug Snake until he decided to rebel and fight back against the Dominion.
Kai Winn is the queen of Smug Snakes, especially in her first appearance.
She and Weyoun actually meet and have a Smug-off in late season five.
St. Elsewhere: Dr. Seth Griffin started out this way, particularly when he tried to pit fellow first year residents Carol Novino and Susan Birch against each other. Birch ends up taking the fall for a patient death for which Griffin was responsible and is kicked out of the residency program.
Storage Wars: Dave Hester acts like a complete prick and has a near-permanent smirk on his face that makes one wonder why the other bidders don't knock his teeth out.
Supernatural: Bela Talbot, a thief and dealer in occult items, was intended to be a Chaotic Neutral foil to the Winchesters. Unfortunately, she was so disdainful and so treacherous (she sells their location to an enemy, steals the Colt, sets up the boys for arrest by the show's Inspector Javert, and finally tries to kill them) that even her tragic backstory couldn't earn her sympathy from the Winchesters.
We have Richard Hatch, Boston Rob, The Four Horsemen, Coach, Colton Cumbie, and Russell Hantz, although the latter tends to be a cross of this and Entitled Bastard.
Richard Hatch and Boston Rob don't count since they both backed up their arrogance by actually winning (albeit it took Rob four times in order to do so. He was definitely a Smug Snake in his first season, but during All Stars he took the leap into Magnificent Bastard territory. Richard on the other hand has always been shown as being very smart). The other examples mentioned above( as well as many others on the show) are, however, justified.
That '70s Show: Laurie Foreman, who was the only somewhat major character with no redeeming moral qualities, a general smugness about her, and was intentionally made this way, with the characters themselves lampshading it.
The Thick of It: Being set in a world of power-crazed politicians, this show has a fair few. Julius Nicholson and Steve Fleming both consider themselves to be Magnificent Bastards but they also have big egos and tend to foil their own devious plans by bragging about them.
Top Gear: Jeremy Clarkson tackles any task or challenge on the show with the attitude that it will work because he says it's going to, even if his co-presenters warn him otherwise. Which makes it all the more hilarious when things go horribly wrong as a result.
Torchwood: Miracle Day: Lyn Peterson. She's very attractive and seems pretty powerful at first, arresting Rex Matheson and the Torchwood team as soon as they arrive on US soil, but her incompetence soon becomes clear when her attempt to poison Jack Harkness is easily exposed and Gwen Cooper incapacitates her with a single punch. She proves herself a good fighter when she assaults Rex, but he still manages to defeat her by breaking her neck. Given that everyone on Earth has lost the ability to die, she remains alive but disturbingly (yet strangely comically) has her head on backwards.
True Blood: The members of the Fellowship of the Sun tend to follow this trait. Filled with empty smiles and holier-than-thou attitudes, this vampire-hating church isn't above kidnapping and murdering of ordinary people whose only crime is having a sexual relationship with a vampire, all while declaring their good intentions and other propaganda. Especially annoying, since many (most?) vampires of the show would most definitely deserve staking, but you couldn't root for these people to do it even if you wanted to.
The Vampire Diaries: The modern John Gilbert. Smug, sadistic, and smarmy, a lot of viewers consider him the only villain they've really wanted to die as soon as possible.
Speaker of the House Haffley is an example of the "failed Magnificent Bastard" variety. He often tries to use the Republican majority in Congress to be irritatingly obstructionist to Democratic president Bartlet. However, often when he is most confident is when he fails terribly (such as when his attempt to cut the budget leads to the government going broke and Haffley look stupid, or when his pulling a vote on stem cell research to interfere with Democratic campaigning leads to Matt Santos tricking him into thinking the Democrats had left when they didn't).
The former example almost works; the government shutdown cripples the United States and the public blames Bartlet... until a Moment Of Awesome where Bartlet walks to Congress to discuss the matter with Haffley - unfortunately for Haffley, he's unprepared for this, his Smug Snake instincts kick in, and he ends up leaving Bartlet sitting in a corridor whilst he tries to figure out what to do. This backfires on him badly when Bartlet merely leaves, making Haffley look incompetent, arrogant and uncaring, causing public opinion to swing into a serious backlash against him and forcing him to eat crow and accept Bartlet's budget terms.
An infrequent recurring character called Larry Claypool represented the 'slimy-but-low-level Obstructive Bureaucrat meets Amoral Attorney' kind; a lawyer for a right-wing organization that frequently sought to embarrass the President by muckracking, he often issues subpoenas to the characters requiring them to testify about issues that will cause embarrassment to the President and his staff, and comes off as smugly as possible whilst doing so. He's frequently described as an idiotic, pompous blowhard, but a dangerous one since he has the unerring ability to find things that might cause serious damage to the administration in his muckraking.
Who Wants to Be a Superhero?: Dr. Dark is intentionally played as this in the second season. He talks in a raspy voice and spends his screentime boasting about how evil and brilliant he is. Then when his big plan in the second season fails, he confronts the superheroes personally and gets beaten up in a fight that lasts about a minute and a half.
It'd be easier to list the antagonists of Spartacus: Blood and Sand that aren't Smug Snakes. Ashur, Glaber, Albinius, Tullius, and Cossutius are some of the more notorious examples.
Played with in Defiance. Niles Pottinger, the man the Earth Republic sent to keep the title city in line, might be a slimeball, but he's also a genuinely clever man perfectly willing to do all sorts of horrific things to get ahead, fully capable of outmaneuvering all the other players in the game. He's not underestimating his own skills, which is part of his problem—everyone he meets hates him because not only is he annoyingly competent, he's smug about it. His superior in the E-Rep even notes that while losing Defiance would be a huge blow to their operations, watching that smirk get wiped off Pottinger's face would be worth it.