Splashtop

http://www.splashtop.com/splashtop_overview.php

When you press the power button or a special hot key designated by your PC manufacturer, Splashtop starts in seconds – it is the first screen that you will see.
Splashtop is preinstalled on the hard drive or in the on-board Flash memory of new PCs and motherboards by their manufacturers. Splashtop is a software-only solution that requires no additional hardware. A small component of Splashtop is embedded in the BIOS of the PC – that’s the part that runs as soon as you press the power button.
Within Splashtop, you have the choice of running one of its applications, such as the Splashtop Web Browser, or booting your Operating System. Splashtop is compatible with any Operating System, including Windows and Linux.
Splashtop has similar networking capabilities to what you find in other Operating Systems. It can connect to networks over WiFi, LAN, xDSL, and cable. WEP, WPA, and WPA2 wireless security standards are supported.