Here's a neat little list of the top 10 films about paranoia over at Wired, in honor of the 10th anniversary of The Matrix. The list is solid, and I was happy to see Dark City on it (an under-rated gem, imo). The Conversation is, rightfully, at the top a true paranoia flick), and my other personal faves include Blade Runner and The Game. Total Recall could of made the list, had the tone been a bit darker, and another that wasn't on the list, but could have been, is Memento. These, and several other good suggestions, were listed in the comments. Enjoy!