This is a limited time offer and you can only choose between Silver and Black. The P2 case is an extended ATX case, so it should fit just about anything apart from some larger dual or quad CPU boards.
It comes with a 700W PSU of unknown origin (no, it won't be from outer space) as well as built in lights in what Alienware refers to as "Astral Blue". The case has front mounted connectors for FireWire, USB 2.0 and a headset.
I can think of a lot of better things to spend US$399 on, but if this is your cup of tea, click here to head over to Alienware