Boston Dynamics, famous for Big Dog (check out the Big Dog youtube video), are now working on a Biped, PETMAN.
Its still early on in the project, but they seem to be making good progress on the mechanical side of things. The noisy motor might prove to be a bit of an issue.
I wonder how long until the japanese fighting-toy robots get to be using this kind of equipment. It's probably still quite some time, since robot prices don't tend to drop too much over the years. I'm predicting it will still be a very long wait till consumers see anything beyond toy bipedal robots.