>>19605418Outrage 1 & 2 are probably my favorites.
Sonatine is great too, a classic.
Tokyo Drifter is less about the yakuza and more about one dude and kino shots, but still great.
Taxi Yakuza for a very cheap v-cinema comedy.
I'd like to say Battles Without Honor & Humanity but those movies kinda blended together in my mind and some are better than others, but they're still worth checking. I should rewatch them at some point.