My favorite is always going to be Delicious. Thanks for creating such a versatile typeface, Jos.

Titillium!
http://www.campivisivi.net/titillium/?page_id=2

Museo and the others from Exljbris
Miso
Some of the ones from the League of Moveable Type
Gentium

Not Titillium!

The fonts from Exlijbris are surprisingly good. this thread has been worth it just for that. I guess thats my way of saying bump

I like the free weights (all the weights) of Galette http://new.myfonts.com/fonts/paragraph/galette/.
This looks good on webpages, distinctive yet very legible.

Thanks Christopher, Riccardo & A-type!

Let's include Gentium, and other productions by SIL and Victor Gaultney.

These are display faces but all of the free fonts on
http://fontfabric.com/
are extremely well designed. Some cool tutorials too.

Jos, you deserve it man, as a poor recent grad its good to have somewhere to turn to get professional looking fonts. Also, I have to admit, that I've been on a downloading binge and I've downloaded pretty much every font mentioned here as well as the ones on the websites mentioned.

recently I have been digging on some block serifs. Museo is one of my favs you can find a link to it here: http://conceptgenius.com/free-fonts-2010/

Try 'fontspring' for some great new free fonts.

http://www.fontspring.com/

Also, 'FontSquirrel'.

http://www.fontsquirrel.com/