In conclusion, we argue that a compact worm that begins with a list including all likely vulnerable addresses, and that has initial knowledge of some vulnerable sites with high-bandwidth links, appears able to infect almost all vulnerable servers on the Internet in less than thirty seconds.
http://www.icir.org/vern/papers/cdc-usenix-sec02/index.html
Gods.. Are ther blackhats offering toasters? That paper is a reminder of the advantage they hold over us...