Nematodes

http://www.eweek.com/article2/0,1895,1867317,00.asp

Interesting story on a potential "alternative" use of computer worms for "good" rather than evil.

"He [Dave Aitel] said nematodes can be automatically created from available vulnerability information and even showed off a new programming language to create the worms."

Not sure this is the way of the future, but...