Gammonet

From Microsys:

Play backgammon with your friends from all over the world. This game version has new 3D boards, many playing options and an intuitive interface. It allows you to play on the Internet with a direct IP connection or using an instant messenger client. You can invite your opponents to play rated or unrated games, having the doubling rules enabled or not; also you can chat during games. Several checker models to choose from, doubling cube, flipping sides, stereo sounds FX and voices are only a few of the other game options. Play for fun and develop your backgammon skills.

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