Masaaki Yuasa's virtuoso powerhouse, Mind Game. If you haven't yet seen this movie, you're missing out on the best animation film of this decade. Probably better suited to artists and day-trippers and the occasional Fellini fan than the typical anime geek, it nontheless remains a must-see for all lovers of the medium.
The Japanese DVD, if I'm not mistaken, includes English subtitles, not that it matters much. You'll be far to distracted by the fantastic imagery to even notice. Mind Game pushes the limits of animation for its own sake, like a Yellow Submarine for the Hip Hop Generation.