Lucas used to talk about another Kurosawa film, "The Hidden Fortress" (1958), as an inspiration for Star Wars. I've seen it, and it isn't really very similar at all, although some of the Japan-ery in Star Wars may be due to Kurosawa's films.

Yojimbo is great, but it is more like a Western in style. That was deliberate on Kurosawa's part, he was a fan of Westerns. The same character that stars in Yojimbo also shows up in "Sanjuro" and one of the films in the Zatoichi series: "Zatoichi to Yojimbo". They all rock.

By the way, the spoiler site was great. Maybe six months or more ago, I ran across a detailed plot synopsis for SWIII, and it looks like it was right on the money. Frankly, I'm glad. Looks like we'll actually have a decent story this time. Plus, lots of light-sabery goodness. I'm still crossing my fingers about the dialogue and acting.