While we've yet to see the rollout of Microsoft's Surface, rumor has it that other versions have at least made it to the prototype stage. According to ZDNET's sources, Microsoft has a "spherical Surface prototype" bouncing around the Redmond campus. What's intriguing is how they managed to stuff a rear projection unit and IR cameras into a ball. Presumably, we're talking about a different touch-sensitive technology to that used in the table-top surface. You know, assuming the rumor is true.