My current company, HelloWorld, hosted a small games jam after hours. Over the course of 5 days, James (another dev at HW) and I put together two small concepts utilizing a networking engine one of my other coworkers wrote
The original concept for my game was platformer where the player must escape a pool of rising lava and race her friends to some sort of goal. The first step was intergrating the networking engine with THREE.js and physics to get 3D aesthetics and correct movement. The actual gameplay is quite shaky due to integration problems and time limitations.