GILES: the Great Internet Ludic Experience Server
Giles is a telnet gaming experience, meant to provide a platform for playing various games both old and new with nothing more complicated than a decent telnet client.
Chances are pretty good that:
telnet bombadil.thenexusproject.org 9435
will connect you to the current testing instance of Giles (unless it's down). You should also feel free to crank it up on your own.
A friendly game of Set.
Kibitzing a game of Y.
Giles is released under the Affero GPL, version 3.
Miniboa is released under the Apache License, version 2.0.
Bitstring is released under the MIT license.