Primer.. Very cool indy film, pretty trippy..

As far as other good movies... Try all Stanley Kubrick films...

Amores Perros (sub-title), pretty interesting movie.

21 Grams. (also directed and written by the same guys that did Amores Perros mentioned above.)

.........

And if u want a funny crazy action movie that was really good when stoned. Ong-Bak the Thai Warrior.... It was kinda silly but well worth the hour or so watching it for a little change.