by Steven J. Vaughan-Nichols - There are several Linux distributions that are designed to help you bring dead PCs back to life no matter what operating system they're running. I have two favorites in this line: Damned Small Linux, which will run on almost any 486 or newer PC, and SystemRescueCD. With both, I've brought PCs back from fried hard drives, corrupt memory, and innumerable cases of Windows malware crud. If you ever do computer repair, you must have at least one of these in your repair kit. They're incredibly powerful and useful.
This tip is adapted from "And the best Linux desktop distro of all is..." by Steven J. Vaughan-Nichols.