Plugable DC-125 USB 2.0 Laptop Docking Station and Multiseat Thin Client - VGA up to 1440x900 / 1280x1024, Audio, 2 USB ports. $64.95 @ Amazon
The impression I get from the article and
linked article is that you can attach one of these "Plugable" devices to one of your computer's USB ports, attach a monitor/keyboard/mouse to the Plugable device, and you have another user seat working off your computer.