GoogleWhack: The challenge of finding a pair of words that will return one - and only one - Google result.
rorriM elgooG: (Google Mirror). The site's backwards; the words you look for also get turned around. Not very useful, but amusing once or twice.
Google Video: Google's latest pet project. For now, they're only chronicling transcripts and screenshots of a few major TV channels, but eventually they also hope to add the recorded streaming video. Think of it as TiGoogleVo. (Wow, this really blows are NDTiVo project out of the water.)
GoogleFight: Like GoogleWar, but with Flash stickman graphics. Looks like Klondike still can't beat his booze habit.
Omnipelagos: As noticed by Klondike. May or may not use Google, but fun anyways. My booze connection.
TouchGraph GoogleBrowser: Draws a map of sites that Google feels are related. Try it with kankasports.blogspot.com, and you'll notice some familiar web friends.
Keyhole: You've seen it on the news. Technically, you've seen it if you've ever used Google Maps in "satellite" mode (it uses the same maps). But, if you sign up for a free 7 day trial, you can do all the zooming animations just like on the TV!
Google Cartography Applet: Kind of a combination of the last two links - it "maps" the streets around your area
