, SecurityFocus 2003-08-19
The Slammer worm penetrated a private computer network at Ohio's Davis-Besse nuclear power plant in January and disabled a safety monitoring system for nearly five hours, despite a belief by plant personnel that the network was protected by a firewall, SecurityFocus has learned.

Anonymous
are due to lazy sysadmins (all platforms), I must say that I'm shocked that there are Nuclear plants critical apps on the MS platform.
A robust Unix cluster with tripwire would be my personal choice....
[ more ]