Sorry, Yet another post for a Acer Revo, but I think this is better value if you want it to run windows.
This one effectively gives you an extra 2gb and a larger hd for £10 on the ebuyer price.
Free delivery too.
There are several Ebuyer deals -
£129 - R3600 230 CPU 1 Gb, 160GB, Linux OS, wired kb/mouse
Link - http://www.hotukdeals.com/item/613479/ebuyer-acer-the-aspirerevo-r3600-wi
£189 - R3610 330 CPU 2GB, 250GB, linux, wired kb/mouse / s/pdif
Link - http://www.hotukdeals.com/item/613702/acer-aspire-revo-r3610-dual-core-94
£239 - R3610 330CPU 2GB, 250gb Windows 7, wireless kb/mouse spdif
£270 R3610 330CPU 4GB, 500gb Windows 7, wireless kb/mouse spdif