From lwn.net:

DesktopLinux.com reviews the 0.4 version of SystemRescueCD, a Gentoo-based distribution for repairing broken systems. "Another major improvement is that you can now use PXE network booting. With PXE, you can boot a troubled PC remote over your LAN into SystemRescueCD. This is great, for example, for a help desk repairing systems scattered over an office or campus. To get this to work, the PCs will need to be set to use wake-on-LAN and network boot. That's been a standard PC feature since 2001, but it usually must be made active in the BIOS before you can use it."

Article at: http://www.desktoplinux.com/news/NS4076782266.html