Some bad ideas seem to live on forever. One of the big ones in computers is to <A HREF="http://www.eweek.com/c/a/Security/Good-Worms-Are-A-Bad-Idea/?kc=EWKNLNAV050608STR3">use hacker tactics to perform white-hat operations</A> on an Internet scale. The classic example of this is the "good worm" idea--a worm that spreads among computers to improve their security.

There have been attempts to do this in the past, most famously Welchia, a worm that exploited the infamous Windows RPC/DCOM network vulnerability in order to patch it. There were also reports years ago of Hewlett-Packard launching a good worm, but this turned out to be a more conventional scanning system that in some ways presaged NAC (Network Admission Control).