This site features lovely details (e.g. your cursor becoming a stylized fox head, vainly chasing “sour” grapes) while presenting good font pairings:
There are over 640 Google web fonts available for free. Problem is, pairing typefaces isn’t easy. And, many of the fonts in Google’s library don’t work well when applied to typical webpage (desktop) layouts. Part of the 25×52 initiative, this collaborative, ongoing project helps provide typographic inspiration for using Google’s web fonts for web applications.