I like this list from Ironic Sans because it's not a list of movies based on merit, which is an incredibly arbitrary and unreliable way to list movies anyway. Instead, this list is about movies that have contributed to either our film history or popular culture. For that reason alone, it's probably a good idea to take a look at them.
This is also a veritable piece of internet history, complied from usenet user suggestions back in 1994 - so it's obviously missing some more recent worthwhile films. If I am so inclined over the next week or so, I might sit down and put together an appendix of my own suggested additions.
For the record - I only scored 109. Now that winter's coming and I won't be outside as much, it's probably about time to raise my Greencine rental plan and start catching up.