YKK
Kafka
Tatami Galaxy
Mushishi
Mononoke (+ last three Ayakashi episodes)
Mind Game
Cowboy Bebop

Shorts:
Genius Party Anthologies
Memories
Short Peace
Animatrix

Artsy:
Iblard Jikan
Kanashimi no Belladonna
1001 nights
Angel's Egg

If you're into their styles:
EVA
FLCL
I liked FLCL a lot as a teenager.
and shit like Kino no Tabi etc...