5)Toy Story - This is a bona fide classic animated film, how can I not live it?!
4)Monty Python's Life of Brian - To me, the funniest of the Python films (that's right, funnier than Holy Grail!), it just holds out stronger as a feature film, plus Graham Chapman definitely delivers in his dead-serious fashion far better than Holy Grail.
3)Alien - A truly frightening horror film, but with equal amounts of focus on the plot, character, and sci-fi elements.
2)A Clockwork Orange - This movie deeply disturbed me the first time I watched it, but it at the same time struck me as a clever, sophisticated commentary on both human nature and our perspective on a "erfect society". Not to mention Malcom McDowell's performance, which is among the greatest things ever captured on film.
1)The Big Lebowski - This film has a quality about it that I just can't resist, it's funny, semi-serious, irreverent, and powerful all at the same time. This is the kind of movie that doesn't try to sell you a message, but simply to entertain, and it pulls that ideal off perfectly! Oh, and just 'cause I can say this... "The Dude abides."
So, there you have it, in my opinion the coolest movies ever made. I tend to gravitate between various genres, but my favourites are usually comedies, thrillers, or sci-fis. You can tell alot about somebody based on the movies they like, you know.