www.alphadictionary.com

I thought I'd revisit this thread and let people know that, 16 years later, the site is still up and running. It's got lots of different trivia sections to play with, along with several different languages you can try your hand at. It's still an easy way to make essentially free donations. All you have to do is spend the time and see the ads. (Though I use an ad-blocker, so I don't see many, if any.)

Another FREE daily way to make donations is: The Literacy Site. The advertisers pay per click to provide free books for kids.