Bruce Schneier talks about how MSBlaster may have affected critical computer systems involved in the east coast blackout:

Let's be fair. I don't know that MSBlast caused the blackout. The report doesn't say that MSBlast caused the blackout. Conventional wisdom is that MSBlast did not cause the blackout. But it's certainly possible that MSBlast contributed to the blackout. The primary and backup computers that hosted the alarm systems failed at the same time MSBlast was attacking Windows computers on the Internet. What operating system were the alarm computers running? Were they on the Internet? These are interesting questions worth knowing the answers to.