Toribash has been around for a few years now, but there is a good chance you haven't heard of it. You probably will however, once the game is finished being ported to WiiWare. Right now, Toribash is just available (for free) for PC's and Macs.
Made by Swedish game-guy Hampus Sderstrm, Toribash is an innovative and interesting ragdoll fighting game. You have a lot of freedom in the game: you can customize your character using credits you win in matches, and you can design your own moves. With the right move you can dismember and cripple your opponent, which is always fun -- for an example of a difficult move to pull off, check this one out below, where one unlucky dude gets his head ripped off, and thrown over eastwards.
There are weekly Toribash tournaments, many with special themes, clans, with a dedicated and active community playing the game. Taking a page from martial arts, players work their way through different belts, the top accolade being 10th Dan. You can also play the game in different styles (such as kick-boxing, and sword fighting.)
So, what do you think? If you want to get your Toribash on you can get'er done right over here.