I took part in a game jam on Saturday, and we won! 
My main collaborator was artist Niall O’Reilly from local game art company DoomCube.
The game runs using HTML5/Canvas, with a node.js websockets server. The ‘render client’ ran on my laptop and players ran the ‘controller client’ on their phones.. this seems like a really nice way to do casual LAN-style multiplayer games, and it’s a configuration I have been thinking about for a few weeks. I just need to figure out a killer party game idea to use it with!
In “Hittin’ Worlds” Each player plays as a planet, in orbit around a sun. Asteroids are flying about, and players have to use their forcefield to deflect them. By using a virtual joystick-style controller on their phone, they orient the forcefield in specific directions.. incoming asteroids get deflected in that direction. The idea is that players fling the rocks at each other while defending themselves.
We also had a really nice piece of custom music written by a guy called Ian, from Athlone/Reading.