While not present in the actual film (unless you count the ice and snow), the most common poster for The Thing (1982) depicts a man with a white radiance emanating from and obscuring his face, implying he was assimilated.
In The Prophecy, the allegedly good angels like Gabriel and Uriel, who express affection abundantly, love kids and can't stand to see people cry, are the villains on an anti-human crusade to destroy and rebuild heaven as it was before the creation of man. The devil has to offer his aid to the humans who end up getting involved in the war (which he does for his own ulterior reasons).
The main villain of the Constantine movie. While the halfblood Gabriel turned out to be the main cause of the problems, Lucifer (Satan) was dressed in an immaculate white business suit and yet was not the major villain.
There was that black goo clinging to his feet, though....
Though you can take it as a moment of fridge brilliance, since Satan was once an angel, who was cast out of Heaven. It's a fitting look for a sullied angel.
In Night Watch and Day Watch, the good guys are called Night Watchers, while the bad guys are called Day Watchers.
This is because the Night Watch are the side of the Light Others, whereas the Day Watch are the side of the Dark Others. The names are literal; Night Watch keeps a watch on the dark, and Day Watch keeps a watch on the light. The books and movies make it clear that when you get down to it, both sides are just people with jobs, and the Night Watch have quite their share of dicks.
The lot of you missed the whole point: the Light Side is just as packed with assholes as the Dark. The main difference is that the Light consists of collectivist hypocrites feigning righteousness and confused idealists who actually buy into their crap, while the Dark is made up of devil may care individualists who do not need to justify anything with fake morality. For example, Dark vampires kill people, but the Light Side gives them hunting licenses to do so.
Realising that Light and Dark are the same in essence is what happens to all older others.
Toy Story 3. Sunnyside Daycare may sound like a nice place, but it's not. Even in its brightest daytime glory it is not. Also, there's the famous quote, referring to almost literal Hellfire:
Rex: "Hey, I can see daylight! We're gonna be OK!"''
Woody: "I don't think that's daylight..."''
In The Godfather Part III, the Vatican is revealed to be in cahoots with the Corleone crime family.
Sunshine (2007). As the Icarus II gets closer to the Sun the latter begins to take on the impression of an all-powerful god, and not a friendly one either. Several people, notably psychiatrist Searle and the Nietzsche Wannabe villain, are affected.
Then there's Galadriel showing why giving her the One Ring would be a bad idea:
Evil!Galadriel: And now at last it comes. You will give me the Ring freely! In place of the Dark Lord you will set up a Queen. And I shall not be dark, but beautiful and terrible as the Morning and the Night! Fair as the Sea and the Sun and the Snow upon the Mountain! Dreadful as the Storm and the Lightning! Stronger than the foundations of the earth. All shall love me and despair.
Saruman the White as listed in the literature section; though he isn't particularly nice looking and is surrounded by dark forces he still has quite some light related symbolism, most notable in the scenes in which Gandalf (then Gandalf the Grey) is present.
In Dragonheart, King Einon always dresses in white in contrast with the hero Bowen who is dressed in Black.
The movie adaptation of the first book of His Dark Materials, The Golden Compass, seems to love this trope, to the point that Mrs Coulter (who was black haired in the books) became blonde (to which the author said: "I was clearly wrong. You sometimes are wrong about your characters. She's blonde. She has to be."), and intercision is not done with a blade as in the books, but with lasers.
Soundwave's robot mode vaguely resembles an angel. His satellite mode (well, at least the toy version) also continues this theme somewhat.
And his car mode in Dark of the Moon as well.
When Edward Dalton parks his car under a tree in the full heat of the day, the whole scene does a great job at equating light with fear.
When we are introduced to the Big Bad in Heroic Trio, he is wearing a gold, glittery outfit and is illuminated in the middle of a dark lair.
Commodus, the villainous emperor in Gladiator, wears a pure white gown while battling the hero Maximus in dark armor in the final battle.
In Kung Fu Panda 2, Lord Shen is a white peacock who is a ruthless conqueror who is perfectly willing to commit genocide on the Giant Pandas to thwart a prophecy and then kill anyone in the way of his ambitions. Chillingly fitting considering that in Chinese culture, white is the color of death.
In a rather bizarre scene from Gordy, the villain is shown with a heavenly, golden glow around him as overlaid footage of what he believes is sabotaged clips of the title pig is being shipped off.
The white-suited humans in their clean, sterile towers in Oblivion 2013 . Sure, they're more-or-less good people, but they're unwittingly maintaining the Tet's ongoing obliteration of humanity. Similarly, the shiny, white, disturbingly Trigger HappyAttack Drones.