Crows Zero, Sukiyaki Western Django, Versus, or Wild Zero.
Crows Zero is a brilliant Japanese movie that follows a manga. The story is wonderful and the fighting is amazing. It's realistic, too. None of that flying on a wire crap. The second movie was just as amazing as the first. Crows Zero is my favorite movie of all time.
http://www.youtube.com/watch?v=EBHXYSSGV8Q
Sukiyaki Western Django is a Japanese western but it's in English. Quentin Tarantino had a hand in it, so you know it's nutty.
http://www.youtube.com/watch?v=nluPs-nGngk
Versus is a zombie action flick. Fighting, guns, zombies, zombies with guns, very odd plot. Very strange and low budget. Also Japanese. This movie is so cheesy and cliche it's actually good.
http://www.youtube.com/watch?v=RUnWKysHpvA
Wild Zero is a movie about space zombies that came to Earth. Easily the weirdest movie I've ever seen. Also Japanese.
http://www.youtube.com/watch?v=YQ_D9OjDoQ0
Yes, I love Japanese movies.