In Dragon Ball Z, all of the main characters can fly. When someone brings out their Super Saiyan Battle Aura, it adds to the mix rising currents of Dramatic Wind and Chunky Updraft lifting stuff up around them as they leave the ground. As an added bonus, this often happened not by having characters rise off the ground, but by having a small section of the ground blown out from under them with their Battle Aura. They simply couldn't be bothered to fall a measly four inches.
Played with in Ah! My Goddess. All the paranormal types can and do float on occasion; however most of these (i.e. Belldandy) aren't especially menacing.
Grove from Vampire Hunter D Bloodlust. When the others need him to, he uses a super powerful spirit form that glows and floats as he attacks. It's quite deadly.
In Mahou Sensei Negima!, it's expected that wizards are to fly using wands or brooms, but at the particularly high levels, anyone may float in the air. (Konoka, Nagi and Fate; Evangeline didn't count, for being a vampire with assumed flight ability). It was even used as a secondary clue that Fate was a high-level opponent ("and, y'know, he's floating").
In Magical Girl Lyrical Nanoha, the forced transformations of Hayate and Vivio into their respective Superpowered Evil Sides were both preceded by their bodies floating in mid-air while surrounded with their overflowing magical energies. Not to mention that pretty much the entire cast list of A's seems to have no problem with standing in thin air. It's like gravity doesn't want to pick a fight with any of them.
Bleach: Subverted. Characters cannot naturally fly in this story, although it does look that way. What they actually do is stand on air. Different spiritual groups have different names for the techniques they use to achieve this, and the techniques themselves can be slightly different. However, it boils down to manipulating the energy particles in air (called reishi) to create a platform of air that the character stands on or runs across. The platform isn't visible (although visible platforms can actually sometimes be created).
There's plenty of Roof Hopping and Le Parkour, but no actual flight; muscular effort is always required. Then the Big Bad is shown hovering in midair above Konoha prior to unleashing his ultimate jutsu. Oh Crap.
Later, it seems like the Tsuchikage had the trope going on, but it turns out that he actually knows a technique that lets him and his subordinates fly.
However, there are many Big Bad class X-villains who are seen flying, even when the other powers they use don't suggest they should be able to.
Black Adam has a tendency to float a few inches above the ground. Such a frequent tendency that he apparently even does it when there's no particular need to be intimidating. Lampshaded when an ally asks him to stop doing it because of how disconcerting it is.
The Sandman also mentions that angels never touch the ground, with the exception of the fallen angel Lucifer of course. When Remiel is forced to take over Hell, after much pleading and whimpering, he is also forced to land.
Just before the final fight in Thief of Time, Newgate/Jeremy floats gently, while glowing. He's learned Rule One — "Never act incautiously when facing a small wrinkly bald smiling old man!" Still doesn't go too well for him.
Ravenor. Stephen Hawking plus psychic powers in a floating wheelchair.
The C'Tan like to slowly float over the battlefield as they kill everything in sight, though this is largely because they consider the laws of physics to be optional. Similarly, the enormously psychicTyranid organisms known as Zoanthropes float to get around, since their brains are superdeveloped at the expense of the rest of their body — their tiny, atrophied legs can't possibly support them. Going by how the models' brains are clearly visible, neither can the rest of their bodies...
Psykers in Dark Heresy et al. can — depending on the circumstances — subvert, invert, or play this trope straight; either intentionally through power use, or accidentally through the Psychic Phenomena and Perils of the Warp tables (in particular, the Falling Upwards result constitutes a very nasty inversion, to say nothing for The Surly Bonds Of Earth)
In Warhammer, the Slaans are huge frog-like creatures, lords of the Lizardmen and most powerful wizards of the earth. They get around by sitting on rock-thrones that hover a few meters above the ground. It is not said if this hovering comes from lost technology or their magical powers.
The Elocater Prestige Class's 1st class ability, "scorn earth," causes you to float a foot off the ground at all times. The ability's description implies that you're so powerful, you've just decided to ignore the ground entirely. In fact it lets you float as high as you like, but at more than 1 foot above the nearest flat surface they lose a lot of speed and stability. Still, nothing is stopping you from floating up to the tower's topmost window and gliding through.
Forgotten Realms has this included in most cases of Power High. The old Mystrylan ceremony of Starflight did this separately... but was often combined with Magefire cleansing ritual into one long Power High trip.
The Ashura of Legend of the Five Rings appear to be samurai with moth wings that float above the ground. Although they are powerful, they aren't deliberately floating — they are so utterly corrupt that the earth itself repels them.
BIONICLE: When Brutaka fell into the Antidermis pool and soaked up the spirits of the unborn Makuta, he gained instant powers and super-knowledge. For the remainder of the story, he floated.
The first of the flight powers is "hover", but it's essentially extremely slow flight. Well, it used to be only that. Recently, it was changed so that instead of just being in the "superman" pose but going comically slow, the character remains upright, with arms held out to the sides. It looks much more badass. And, of course, it can be used to invoke the trope: a very high level, powerful character who suddenly starts hovering above the ground can be, depending upon what they're saying, a visual shorthand for "you REALLY should be respecting me more" to "don't worry about it, I'll clear the entire map."
There is also the Soul Storm power, which will raise the user into the air, flight or no flight.
Final Form in Kingdom Hearts II. Apparently this is because you only unlock Final Form after completely merging with Roxas by defeating him in a fight. Yes, Roxas can float. And summon pillars of light. They never explain why. Since Final Form is formed from a combination of Sora and Roxas, Sora inherits the ability to float.
Wisdom Form also has a little bit of float to it as well.
Also from Kingdom Hearts, Riku/Ansem from the first game. Coupled with Riku's echo-y voice and new outfit, this just screamed that you were in for one hell of a fight.
When you play as Xemnas in 358/2 Days he does not walk as the other characters do, but floats instead.
Duke in the battle against him in Tales of Vesperia. Rita can also get in on the floating with her Levitate ability, though it rapidly expends TP while it's active, due to being able to levitate out of the reach of many enemies. Estelle does it in both of her Hi-Ougis, as well.
And The Sorrow from MGS3, although he is technically a ghost.
Tons of powerups and other items in videogames, especially networked deathmatch franchises like Quake and Unreal Tournament.
While it's not really floating as much as it is slowing her fall, Justicar Samara from Mass Effect 2 can use her biotics to float herself through the air for short periods of time. Given that she can send hundreds of Collectors flying with some effort, she could probably support herself for a while. Why she would is another question.
Joshua at first appears to be just a white haired Bisonen with a magic cell phone, and no real athletic prowess. However, about midway through his chapter, he reveals that he's actually much more powerful then he lets on. While in Levitate Mode, Joshua is arguably one of the most powerful partners in the game, and his Jesus Beams are much more powerful than his standard ground combo. Of course, it only makes sense that he can float because he is Shibuya's Composer. They don't call them Jesus Beams for nothing.
In Command & Conquer: Red Alert 3, the Empire of the Rising Sun has a special unit named Yuriko Omega who can float. Her unit description? It basically boils down to "she floats because she enjoys rubbing in the fact that she can kill us mere humans with her mind." This does have a practical purpose in that it allows her to cross water at a reasonable speed. (Other commando-class units have had extensive swimming training; her "education" didn't include much in the way of P.E.)
In Sword of Mana, when you finally get to fight Julius, he floats a few inches off the ground. This is before he actually goes One-Winged Angel, but then, his Vandole blood has basically taken him over by now, and he's also leeched most of the Mana Tree's power too.
Characters casting high-level magic will rise to a foot or so off the ground for the duration of the spell. Magus, a powerful sorcerer, prefers to skim along just above the ground in a dramatic pose, since running is apparently for chumps.
Dark Samus from Metroid Prime qualifies quite adequately, also displaying an ability for full-scale flight in the third game.
Every time Samus got a new suit in Metroid Prime 1 and 2, she would rise into the air while glowing energy surrounded her and she equipped the suit. In Metroid Prime 3, this was reserved for when she released phazon into Leviathan cores, again glowing, but this time with phazon.
Her Final Smash in Zero Suit form in Super Smash Bros. Brawl involves getting her Power Suit back (as well as dealing massive damage to anyone unlucky enough to be standing next to her during it), so it also has her floating as the suit's pieces form around her.
Polvakian Gem Slugs in Startopia are so rich, lazy, and haughty that they loco-mote on hovering wheelchairs.
Azure Kite very, very rarely walks, or even stands. He just floats two inches off the ground, even when you later get to recruit him into your party.
None of the Avatars walk either; when an Epitaph User summons one, he appears to be floating (Avatars themselves are invisible to normal players).
In Final Fantasy XI, float is forbidden magic, so only certain very bad, Badass characters can actually float. This includes the Arcangel Tarutaru, Kam'lanaut, and Eald'narche. Not to be out done the Big Bad from the Wings of the Goddess expansion, Lady Lilith, is so Bad Ass that she can actually fly. On the good side, Selh'teus can fly because he bonded with the Terrestrial Avatar Phoenix.
In Neverwinter Nights 2, anytime a high-level wizard or mage character casts a high-level spell, they levitate several a foot or so off the ground while performing the spell. The other two powers also occur, as the character gets a glow around them and the chants start to echo.
In Mega Man X8, Lumine spends the entirety of his first battle phase floating around the battlefield in a figure eight pattern.
In Touhou Hisoutensoku Yuyuko, Iku, Cirno, and Utsuho only ever touch the ground when crouching or knocked down. Of these, Cirno is a definite non-example, only being especially powerful by fairy standards. Utsuho is the strongest example, having no particular reason to float other than being badass.
In the Valkyrie Profile games, the bonus character, Freya, is always floating off the ground, and is usually one of the most powerful people you can add to your party (or, similarly, one of the most powerful bosses you can face).
Otani Yoshitsugu from Sengoku Basara sits in a floating palanquin and attacks with floating prayer beads he manipulates with his Mind over Matter powers. The only times he ever touches the ground is if you knock him down or kill him.
While all the Deities in Asura's Wrath can fly, Karlow levitates on low ground, and can even flip upside down.
In Jak and Daxter: The Precursor Legacy Gol Acheron and his sister Maia are only ever seen floating. Gol even has weights tied to his waist, probably to prevent him from drifting off.
Neptunia: You'll never see a CPU or CPU Candidate actually using their feet when they've activated HDD.
In The Last Story, anyone casting a spell will float for a few seconds.
In Devil Survivor, you see Naoya doing this on routes where you fight him. Whether it's because of his powers or if it's just a reference to his preference for demons that have Flight, Devil Speed and Phantasma isn't certain.
The High Templars of StarCraft float, leave glow-y afterimages as they move and echo while they speak. They are arguably the most powerful casters in the game and one the most powerful characters in the games' lore was one of them. Two High Templars can also merge and form an Archon, one of the absolutely most powerful units in the game, and adds a much deeper voice to the already impressive list of clue-ins concerning their powers.
The expansion, Brood War, also adds the merged form of two Dark Templars; the Dark Archons, beings with powers so immense they can completely mindwipe any unit that gets in their way. Ulrezaj, another one of the grossly overpowered characters in the games' lore, is a Dark Archon formed by the merging of seven Dark Templars. He is closer to an Eldritch Abomination with the potential to invoke a Cosmic Horror Story more than he is a Protoss.
In the sequel, the Hybrid Destroyers float all the time and are incredibly powerful being Protoss/Zerg hybrids that more closely take after their Protoss heritage. They're basically Protoss Templars on steroids.
In Sluggy Freelance, Gwynn tends to float and glow when she starts really channeling her witchy powers.
Magick Chicks has a scene where Melissa requests power from Genius Loci and receives a wand. After touching it, she is found unconscious, floating in midair inside a hamster-ball of force and whirl of sparkles. When the girl who fought her approached, she gets encased in another floating hamsterball.
The villain of Princess Gwenevere and the Jewel Riders, Lady Kale, once managed to take over most of the magic in Avalon and rule the kingdom. When the Jewel Riders broke into the Crystal Palace, they found her at Queen Anya's throne — or more specifically, "sitting" on it by floating high above.
The Rooster Talisman in Jackie Chan Adventures grants the user levitation and telekinesis. Anyone using it ends up floating pretty much constantly. Other characters also invoke the trope on occasion too, such as Tso Lan the Moon Demon and Drago in the series finale after he aquires all of the Demon Chi powers.
According to the French wolves specialist Gérard Ménatory, the bipedal position of humans is, in the eyes of the wolves, the equivalent of Power floats and the reason why they are scared by us and never stay close to big humans settlement: "Since this animal can casually stand, walk, and run with only two paws, they must be insanely strong and we better not mess with them" was what he claimed to be the basic reasoning of wolves. Considering the man spent most of his life living with wolves and could literally summon wolf packs by howling he certainly knew what he was talking about. (Maybe it's because the only other thing that can stand on two legs in a wolf's natural habitat is a bear.)
However, it's all a matter of image since, according to the same man, an unarmed man has absolutely no chance to prevail in a fight against an adult wolf, especially if said wolf is a female with cubs. Though some combat martial arts taught to special forces and commandos include techniques for use against guard dogs; these ones are useful against wolves, too.