SynJam is a free multiplayer game where players perform and compose music together in real time. Up to eight performers may take part, and results are saved as MIDI files. The game also acts as a multiplayer MIDI file editor/player and multitrack editing studio.

This game is part of the Synthetic Reality "Arcadia" family of games. (http://www.synthetic-reality.com/arcadia.htm) Players add additional channels at will using the integrated MIX server. Arcadia itself provides all networking support, in addition to text chat, voice chat, web browsing, and a parallel existence 'park' environment for serenity, duck-feeding, and paintball while you wait for other players to show up. Arcadia allows you to create a personal identity with which to expose your current emotional state, and maintain a diary of other players you have met in the game.