That's about $400 usd... what would it be used for... gaming? So many different options for different uses. If I wanted it for gaming I would get a cheap case, no optical drive, either a pentium or an i3 sandy bridge, $50ish micro atx motherboard, 4GB ram, <500w psu, and the cheapest HDD I could find. Then I would use whatever I had leftover for the GPU.
Alrighty, heres what I got. $400.93 or 254.96 pounds. This is for someone with gaming in mind. No optical drive or OS included. They could just install windows via usb and use steam or some other client for games.