ContraPloy
Free, turn-based, two-player strategy board game with hidden piece values that change with terrain. Includes annual tournament and message board.
http://www.contraploy.com/

CrossCheck
Slide pieces down the intersecting slots to be the first player to get four in a row in this online strategy board game. Played against the computer.
http://www.sapello.com/crosscheck/

Final Conquest
Multiplayer strategy game of world conquest similar to Risk. Offers rules, FAQ, rankings, and forum.
http://www.finalconquest.com

Pacru
Strategic board game playable by two to four players. Also offers single player game against the computer. Includes rules and downloadable game for offline play.
http://www.pacru.com/

ShopHub.com Word Demon
A fast paced game in which you create as many words as possible out of letters on the board.
http://www.shophub.com/worddemon.cfm

Star Fleet Battles Online
SFB Online is an internet-based Star Fleet Battles tournament game service. Subscribers will be able to play SFB tournament games over the internet with SFB players around the world.
http://www.sfbonline.com