Open Sans title and Gentium Basic body

History of Typography--informative
Useful for designers, the site has a wonderful list of the best available free fonts.
Higher Font: Created by Portugal-based graphic designer Marissa Passos, free font Higher was made as a student project during her time at the University of Porto. The typeface contains a full set of uppercase characters and numbers 0-9. It's free for both personal and commercial use.
Humorous list of type faces and their personality on Flickr at Typocalypse, created by Lars Willem Veldkamp.