the FitPC2 might suit your needs:

Full-featured PC, tiny and power saving
Intel Atom Z530 CPU @ 1.6 GHz
Intel US15W chipset
1GB DDR2
160GB SATA harddisk, easily upgradeable
DVI Digital display interface, up to 1920x1080
HD Audio, line-out 2.0 / mic in / line-in
1000Mb/s Ethernet port
802.11g WiFi
Six USB 2.0 ports
miniSD and mini PCI Express sockets
IR receiver
Phoenix BIOS
Single 12V supply, 6W, fanless operation
Dimensions - 115 x 101 x 27mm
Runs Windows XP, Vista, Windows 7 and Linux
Also available as SBC without enclosure
$380 at Amazon
or the Acer Revo, similar specification, better graphics (nVidia ION), pricing starts at $199 but larger in size and more power-consuming.
