I always play here www.chess.com/
Here are some suggestions:
Sign up for a Yahoo!ID and then head for the Games home page
Another popular haunt for chess players of all levels. Three modes of play: Casual friendly matches, competitive and tournaments and special events
Tim Mann www.tim-mann.org
Good site with links to free chess servers all around the world
Gameknot Free online chess community. No software to download. Multiplayer, solo and real-time blitz chess
Iwin.com Free trial of chess software packages and a range of other games
Chessworld.net Friendly chess community with over 100,000 members worldwide. Good place to learn from scratch
Chess Maniac ChessManiac.com is a free online chess playing community where you can play chess online, participate in tournaments, teams, chess clubs and more.
ChessHere ChessHere.com is an online chess server where you can play online chess against chess players from across the globe. ChessHere is oriented to correspondence chess play. Real time chess (or blitz chess) is also available.