They can build you a computer in whatever configuration you want. And you get to select from some hip colors for your case, monitor and keyboard. They can even paint the speakers. They do come with a slightly premium price though.
I have a Dell 8200. It's black/grey, along with the monitor, speakers, and scanner. I agree. White or beige is a bit boring. I like the way mine looks. But I admit it doesn't look as happenin' as an Alienware custom job.