The holy grail of PC cleaning. But while in your times
rm -rf /
was sufficient. But now you need to do
rm -rf / --no-preserve-root
so that idiots wouldn't delete their entire system, or rather "unlink" their entire system.
But as the ancient Unix legend goes; "as long as you are logged in, the system is not dead yet."
"By now we had been joined by Alasdair, our resident UNIX guru, and as luck would have it, someone who knows VAX assembler. So our plan became this: write a program in assembler which would either rename /tmp to /etc, or make /etc, assemble it on another VAX, uuencode it, type in the uuencoded file using my gnu, uudecode it (some bright spark had thought to put uudecode in /usr/bin), run it, and hey presto, it would all be plain sailing from there. By yet another miracle of good fortune, the terminal from which the damage had been done was still su'd to root (su is in /bin, remember?), so at least we stood a chance of all this working." Unix Recovery Legend