Volity provides libraries in Perl and Python. These aren’t so much for creating the settings, pieces, rules, or moves of a game (those are all game-specific, and you do them on your own), but for the wrapping that makes it possible to sign up players and get them communicating.
With Volity, for instance, gamers can easily search for other gamers and invite them to games. Volity handles all the messages passed between gamers, and does so quickly and efficiently, although it’s not designed for intensive twitch-based gaming (as Jason called it) with real-time requirements. Gamers can chat while playing. A reputation system is being developed (personally, I think that will be the hardest part). How many people need an open-source platform for game development? Well, you might realize–as Jason did two and a half years ago–that there is no other platform that makes it easy to handle multiplayer interactions to develop what the industry calls casual games. This term refers to games played by people for a few hours a week instead of being played as a passion–games for people such as my teenage daughter when she still had free time in her day and would spend an hour on Yahoo! playing Othello or Hearts as a break from homework.
Casual gamers are a much larger population than the hard-core video gamers (and broader demographically, with older people and more women), and they’re beginning to get the attention their size deserves in the game industry.
You might also welcome (as I do) a completely open-source stack for developing interactive environments, because they might be useful for other kinds of collaborations besides games.
Volity components and dependencies read like a checklist for the free software movement:
Volity itself is a set of Perl and Python libraries for development.
Its chat features are based on Jabber, which gained serious market acceptance when Google adopted it for its chat system.
Its graphics are SVG-based.
Its user client, Gamut, is written in Java.