You've played the video game, now watch the movie. Onechanbara was released on DVD today and features women in bikinis killing zombies. Here's the official summary:
In the year 20XX, scientifically created zombies roam the world in record numbers. Despite this, Aya is determined to track down her father's killer, a person who was once close to her. With sword in hand and wearing nothing but her trademark bikini and cowboy hat, she sets off to settle the score. Aya is joined on her path to vengeance by the chubby Katsuji and the gun-toting Reika. Together, they hack, slash, and shoot their way through a sea of the undead to reach the final showdown with a mad scientist and the destined duel with Aya's own sister.
Sounds like way too much plot. The trailer has lots of blood, zombies and wire-fu but not nearly enough bikinis. You can pick up a copy here.