1.Pans Labyrinth
2.Oldboy
3.Downfall
4.Ammores Perros
5.Seven Samurai
6.Pusher
7.The Lives of Others
8.Switchblade romance
9.A Bittersweet Life
10.Zatoichi

My top 20 would be something like this
The Motorcyle diaries
Funny Games
The Host
Frontiers
The counterfeiters
REC
No man's land
Assembly
Audition
Hard Boiled/A better Tomorrow/Ichi The Killer

What's yours? maybe suggest other good foreign films for me to watch