Google Fonts - Making the web more beautiful, fast, and open through great typography
FontFace ninja - A browser extension to identify and try fonts on any website
Typewolf - Typewolf helps designers choose the perfect font combination for their next design project—features web fonts in the wild, font recommendations and learning resources.
FontJoy - Get smart font pairings in one click
Font Generator - Tons of font ideas in one click
FontPiker - Download best fonts, free fonts for personal or commercial use.