You need to restart your computer. Hold down the power button for several seconds or press the Restart button.I did a little research and found the error to be the new 10.2 kernel panic screen. A little more reading on the Apple forums provided a suggestion to remove the Microsoft mouse and use the original one button Apple mouse. That worked, and I've had no other panics, but I thought the following article from Apple's Knowledge Base might be a good reference for others who have been having similar problems or getting this new mesage and pulling a Feiss:
All about Kernel Panics
[Editor's note: I've been meaning to write a brief blurb on the fancy new kernel panic screen for a few months now ... someone beat me to the punch! If you haven't had a panic in Jaguar yet, check out the Knowledge Base article for a screenshot. It's definitely nicer than the black and white screen of death, but it's still a bit shocking the first time it happens -- I know I was quite surprised when my iBook politely informed me it needed to be restarted!]

