Aeon Flux. I know it's awful, my friends all tell me it's awful but I enjoy it! And Charlize Theron in a cat suit is quite frankly awesome.
I actually made the mistake of buying the film thinking "how bad can it really be, it's got Charlize Theron in it and she's a decent actress". I've never been tempted to watch it again, not even just to see if it is as bad as I thought on first watch.
Dark City is an odd one which puts people off with its badly done aliens, effects and general cheese, but I think its great.
I think Keifer Sutherland puts me off more than anything else with his abysmal accent, I'm still not sure what it was meant to be.
A few films from my collection that few people seem to know about but I enjoy are:
Poolhall Junkies - written, directed and starred in by Mars Callaghan, it also features Christopher Walken, Rod Steiger, Chazz Palmintieri and Glenn Plummer. Sharply written with a reasonable enough storyline despite what is clearly a fairly small budget.
Point Blank - not to be confused with Grosse Pointe Blank, this is a fairly brutal film with Lee Marvin as an ice cold hitman getting revenge on the men who've stiffed him out of his money in a double-cross. Subsequently remade as Payback with Mel Gibson which incidentally isn't a terrible film.
Grand Theft Parsons - ok it stars Johnny Knoxville but it's actually a decent film and a good black comedy loosely based on the death of Gram Parsons and the promise that his friend/manager Phil Kaufman made to him about his wishes in death.
Small Faces - entertaining black comedy/drama set in Glasgow about three brothers and the gang warfare of the '60s. It stars a young(ish) Kevin McKidd and some very good performances from the rest of the cast, as Mr McKidd himself says in the film "you've got to hand it to them, that's a remarkable family".