Okay just to clear up a few little problem with the above statements..
Illusion, the xbox power supply can accept from 110v to 240v AC at either 50 or 60hz, hence the power supply you get in your xbox is exactly the same as the yanks get.
jimmy_mac, It would only be black and white if you use composite video, if you use component (scart, RGB the lead the xbox comes with !!) the it will be full colour !
Leeroy, US systems do run on 110v, but you can order PCs if you want, the PSU on the back ususally have a 240v/110v switch, all you need to do is switch that and your fine ! I would say about 80-90% of the stuff (dvd players etc) will work no problem in the UK as they have adaptive Power supplies like the xbox which will accept a wide range of source power, one exeption to this is GHD hair straigtners (no they arent mine, but im going to florida and the GF asked me to check her stuff to see if it would work over there)
1.6 16v, I still have the mains invertor from my xbox install, if you want it I will see you it cheap or something cause I dont want it anymore, it will more than handle an Xbox/PS2 and you can use if for other things too. PM me if your intersted.