Little Golem
Play online board games against opponents. Games include Chess, Go, Reversi, Hex, Twixt, Gomoku, and Four in a Row. Includes tournaments and message forum.
http://www.littlegolem.net/jsp/index.jsp

You Play It
Offers online multiplayer versions of the board games Blue Max and Cartagena. Includes message forum, player statistics and rankings.
http://www.youplay.it/play/main.asp

Darkfish Games
Selection of Java board games playable against the computer. Includes Checkers, Reversi, Five Field Kono, Nim Skulls, Pentalpha, and Taxi.
http://www.darkfish.com/

Game Colony
Multi-player realtime games online. Chat with other players.
http://www.gamecolony.com

The Game Room
Play classic board games, like chess, draughts and backgammon or test yourself with brain teasers, puzzles and trivia.
http://www.thirdage.com/living/games/

Games Park
A multi-player game site featuring Chess, Checkers, Backgammon and Reversi. Uses shockwave plugin.
http://www.gamespark.com

GameSite 2000
Play Backgammon, Chess and Reversi online.
http://www.gamesite2000.com

GoldToken.com Games
Play free online board games like chess, checkers, backgammon, and reversi.
http://www.goldtoken.com/

ItsYourTurn.com
No downloads, no java, just free turn-based (not live) games with thousands of opponents. Play 30+ games and variations: chess, checkers, reversi, battleboats, backgammon, pente, and stack4. WebTV and set-top box compatible.
http://www.itsyourturn.com/

JavaScripter.net
Offers Tetris, Minesweeper, Conway's Game of Life, Snakes, Five-in-a-Row, Set-to-Zero, and Close-All-Books. JavaScript games you play solo (no internet challengers).
http://www.javascripter.net/games/index.htm

The Procrastinator's Paradise
Sad little online java boards games. Play right online no downloaded needed. This page is a great place to have fun and waste time. Includes such games as Hold Your Breath, Tic-Tac-Toe, and Guess the Number.
http://www.geocities.com/TimesSquare/Metro/6209/

Thinks.com
Free online games and puzzles, including many old favorites such as Checkers, Connect 4, Mastermind, Reversi, Hare and Hounds.
http://thinks.com/games/

Vinco Online Games
Offers games such as Backgammon, Chess, Checkers, and Othello. Multiplayer option includes team play.
http://www.vogclub.com/

Kulkmann's G@mebox
Frank Schulte-Kulkmann's Internet Gaming Guide and online magazine. Mostly board games with a couple of war games.
http://www.solicitor.de/gamebox

Atlantic Games
Offers online correspondence games including Chess, Checkers, Reversi, and variants. Includes tournaments, rankings, and upgraded membership option.
http://www.atlanticgames.net/

VietSon
Offers Chinese Chess and the Vietnamese five-in-a-row game Caro playable against the computer or another player. Includes player records and downloadable versions.
http://www.vietson.com/games/

BrainKing.com
Turn-based board games against live opponents including Chess, Checkers, Backgammon, Reversi, and Five in Line. Includes teams, tournaments, and chat.
http://brainking.com/

BrettspielWelt
Play over 70 board games (including Carcassonne, Cartagena and Trans America) either in your browser or using a separate client. [German, English]
http://www.brettspielwelt.de