Where's George?!

http://www.wheresgeorge.com/

On this website, folks can track paper currency (US and Canadian dollars) as they circulate around the US. You enter a few numbers from the bill, mark it with a stamp (as at left) or hand write a note to let people know to register the bill on the site, and go spend it, hoping someone will register a "hit" for your bill. Pretty awesome, and kind of fun when you find bills other people have entered and you can look up where it's been. The website is a little clunky (though it has improved a little over the years) but it's pretty entertaining. Requires registration, but it's free.

Background Maker

http://bgmaker.ventdaval.com/

Here you can make your very own designs that can be used for website backgrounds, desktop images, etc. I have a lot of fun just playing with the tool when I'm feeling artsy-bored. Beware: while it can be therapeutic, it's also rather addictive!

Divorce Cakes

http://cakelava.blogspot.com/2008/08/divorce-cakes.html
Wow. Just... wow. I didn't even know people MADE these. But then I guess any excuse for cake is a good one, right? hehe

Postcrossing

http://www.postcrossing.com

RATHER addictive. Sign up, create an account, send some postcards, and get some back from people all over the world! Since I collect postcards this is a pretty darn awesome site for me. :)

mcsweeney's internet tendency

http://www.mcsweeneys.net/
Lots of cleverly-written stuff here.
Good when bored or in need of inspiration.
English major or literary nerdiness a plus.