KBAlertz
I know some of you guys've blogged about KBAlertz, but I just signed up recently and I had to pass it on.
First, the site is run by Dave Wanta, just for all us folks that need to keep up on Microsoft Knowledge Base articles. Check off all the topics you're interested in, and you'll get an email alert anytime Microsoft publishes a new KB or Support article!
Scott Cate mentioned it at the last AZDNUG meeting as one of those tools he can't live without. I totally second that.
Side note: Dave Wanta's coming to AZDNUG September 16. If you live in or near Arizona, I'd get there.