Google Fonts - Making the web more beautiful, fast, and open through great typography
Fonts Ninja - Try fonts discovered on websites in any design software
Fonts In Use - Type in the real world: an amazing archive of typography.
What Font Is - Find any font from any image (commercial or free)
Delta Fonts - Archive of logo fonts, music fonts, sports fonts and more
Find my Font - Identify any free or commercial font with your camera!