Spring RTS Engine

Id like to build a machine that takes up, very little power, very cheap, doesnt need to have so much horsepower in it, that I can preferably run something lightweight on it such as a stripped down ubuntu etc, without resorting to something like a linksys NAS or those tiny arm based computers that have built in power sockets

The budget is £100-200, bonus points for the cheapest build possible, monitor/keyboard/mouse are exempt, integrated graphics are fine, 1GB of DDR should suffice, and I'm fine with booting off a large usb drive

Any reccomendations? What do you guys use?

Zotac IONITX-A

Aha an atom mobo, I looked on ebuyer.com and totted up the following:



tho the mini ITX case and psu seem a bit much =/