These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Mostly of Anton Chigurh. Those characters who know about him act like he's an unstoppable badass, but think about it. Sure, he kills plenty of people, but always by taking them by surprise/attacking them while they're unarmed/using an exotic weapon that most people wouldn't recognize/all three at once. When he finally confronts someone who is ready and able to put up a fight, he is wounded and loses his quarry. When he is faced with the prospect of a fight with Sheriff Bell, he runs away. Finally, at the end of the movie he murders Moss' innocent and unarmed wife, and then just barely escapes the police with the help of two children. The guy isn't a badass; he's just a cowardly psycho with delusions of magnificence.
He's also a scarily good planner. The scene in the hotel allows him to figure out how to attack the Mexican's hotel room down to every detail. Doesn't make him necessarily any more badass, just makes him good at figuring out his arenas.
Is Sheriff Bell the last of a dying brand of justice, incapable of containing a rising tide of evil, or a self-pitying old man so preoccupied with the past that he has become ineffectual in the present?
Complete Monster: AntonChigurh strangles a cop to death with cuffs; shoots both his employers in cold blood because he wanted the money they were chasing after; shoots a crying, surrendering man hiding in a shower; and has absolutely no qualms about killing innocent people, including a random old man for his car and a motorist that did nothing except pick up the main character. In his most senselessly cruel act, he murders the dead protagonist's wife only to fulfill a pointless promise to him. Even knowing Anton Chigurh puts you in mortal danger. Like one line by Carson Wells points out: "Even if you gave him the money, he would still kill you just for...inconveniencing him." The worst thing about him is how he subjects his victims to a bizarre form of Mind Rape and actually convinces them to accept their death. It's easy to see why his partner-in-crime Carson Wells compares him to the Bubonic Plague. He faces no repercussions, which goes chillingly well along with the nature of his character: an unstoppable force of nature personified in human flesh. He does not even enjoy these acts; he is just an evil psychopath with utterly no regard for the lives of anyone.
Crowning Music of Awesome: After almost exclusively diegetic music note that is, only music from an identifiable onscreen source for the whole film (and barely any of it, at that), Carter Burwell's bone-chilling theme finally plays during the credits, and it is perfect. Unfortunately, it's almost impossible to hear without simply playing the scene over and over on your DVD, because no soundtrack was released. It can, however, be heard in its entirety on Youtube here.
Designated Hero: Moss is unusual in that he seems to be a deliberate example of this trope. He is impulsive, prideful, greedy, and his actions get a lot of innocent people killed as well as ensuring his own doom. However, we are not supposed to see him as a hero so much as a greedy, stupid man in a situation far out of his depth. The only thing he really has going for him is that the man chasing him is a lot worse.
Fashion-Victim Villain: Regarding the haircut, in the actor's words, "I'm not going to be laid for three months." Unlike most examples of the trope, it actually makes Anton scarier instead of laughable.
"Funny Aneurysm" Moment: In the novel Ed Tom Bell mentions the murder of a federal judge in San Antonio. He's referring to John Howland Wood, who was assassinated outside his townhouse by a contract killer named Charles Harrelson on May 29, 1979. Woody Harrelson (yes, the son of Charles) would go on to co-star in the film version of the novel.
Hilarious in Hindsight: Josh Brolin and Tommy Lee Jones co-starred in Men In Black 3, with Brolin playing an uncanny younger version of Jones. This means this is another film where they don't share a scene together.
Moral Event Horizon: The Mexican mobsters cross it when they murder the woman by the hotel pool in their attempt to kill Moss. Chigurh also kills anyone who gets in his way as he moves around the country, and in one case kills an innocent person purely on principle.
"Can you get those chicken crates out of the bed?"
One-Scene Wonder: Stephen Root's character, the mysterious boss who hires Carson Wells, is never named and has only two scenes.
The cop at the beginning. How bad at your job do you have to be to nonchalantly turn your back on a suspect whose mobility is in no way impaired? Never mind strangulation by handcuffs, he could have just as easily sneaked out the door.
The victim whose car is stolen shortly after the above. What was this guy thinking? "Guy in cop car pulls me over, looks like death personified, no badge, carrying a white fire extinguisher thingy. Seems legit."
The Woobie: Carla Jean Moss. Is completely innocent, has a Jerkass husband whom orders her around without telling her anything, and a useless old mother with cancer. Her husband is killed because of his hubris, her mother dies of cancer, and she is finally killed herself by Chigurh.