Heard about this on the latest Elixir Fountain podcast - looks like good fun! 
MOB PROGRAMMING
All the brilliant people working on the same thing, at the same time, in the same space, and on the same computer
Basically, you have a team up to 5 people with one person at the computer (the ‘driver’) and everyone else chipping in on what to do/how to get whatever needs doing done and everyone taking it in turns to be the driver every 15 minutes or so.