It's been a long time since I used it now (probably should get back in the game again), but Flickchart is a pretty fun movie site. The basis is that two movies show up and you have to pick one of them, no matter how hard the choice is (and believe me, sometimes it is really, really hard).
This is my Top 20 Movies of All Time, according to Flickchart. I'm going to get back in the proverbial saddle, so expect this list to change (and be updated with notes) soon.
I'll be updating the list on the first of each month. All the old versions of the list will be in the description.