I would say in no particular order:
The Shawshank Redemption : I loved it, it has some strong characters and good acting and was well put together.
Spongebob Squarepants: The Movie (seriously) : Funny as hell, childish, yes, but the only thing with David Hasselhoff I'll enjoy. Oh and the song at the end, I had goosebumps.
Battle Royale I & II: I felt they were interesting movies - it had some good main characters. The second one was different, but still good.
Machine Girl : Just because of the drill bra, pure genius
Survive Style 5 Plus: Perhaps one of the strangest. I never imagined Vinnie Jones in a crazy random Japanese movie talking to a piece of broccoli.
Children Of Men : I've never read the book and a friend assures me that it is a great book too. The film is fantastic, I quite like the ending too - first you think, "is that it?" and then realise that it could be no other way without ruining it.
The Rocky Horror Picture Show : Come on, "I'm a sweet transvestite from, transexual Transylvania!" As bizarre and mad as this film is (and considered erotic in the 70s, but it nothing now) it is a stroke of genius.
A Clockwork Orange : A classic film and a classic novel, though I've not finished the novel. I viddied the film again the other night.
Fear and Loathing in Las Vegas : What amazes me is that it's a true story and that the book was an actual piece of gonzo journalism looking at the effects of drugs. Johnny Depp does a good performance in it and you really do feel like you're on drugs afterwards. (not that I'd know what it's like, but your mind is perhaps a little warped by it) The film is very close to the book.
Fight Club : I've not read the book, but the film is well made and I quite like the twist at the end. I'd say more but I'd be breaking the first rule of fight club: do not talk about Fight Club.
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Oolite reminded me of 2 others
Forrest Gump and
Saving Private Ryan. The latter is perhaps the best WW2 film I've ever seen and the former is just different, yet a really enjoyable film to watch.
I'm indecisive when it comes to choosing favourites when there are so many to choose from, so lists tend to suffice.