Talking about those Y2K glitches (kidding), the Google Calculator seemed to have stopped working yesterday, all of a sudden. I tried it on New Years and it did not work. But this morning, it appears to be working again.
A search on 2+2 typically brought back a response from Google that looked like:
But yesterday, it just returned weird web results.
It seems like it was down for about 7 hours or so yesterday, based on tracking this Digg post.
Forum discussion at WebmasterWorld.