Getting a Roomba to obey gesture commands turns out to be pretty simple thanks to the magic of Kinect: the sensor is connected to a PC, which talks to the Roomba via a little Bluetooth dongle and sends it driving and steering commands based on the positions of your hands and hips.
I'm well aware that this hack basically defeats the entire purpose of having a Roomba, without really giving you many of the benefits of an upright vacuum, but to let those facts bother you would go against the spirit of what this is: it's a hands-free Roomba, man! How cool is that?
Evan Ackerman is a senior editor at IEEE Spectrum. Since 2007, he has written over 6,000 articles on robotics and technology. He has a degree in Martian geology and is excellent at playing bagpipes.