While not quite as ballsy as riding around on a motorised couch for funzies, the sofa bike is cool for taking the idea and running about as far as you could go with it.
Designer Jacek Holubowicz basically combined a loveseat with a tandem bicycle for this concept. And then he went crazy with it. The couch has two separate 8-gear hubs, hydraulic brakes controlled by the sleek handlebar on the arm, a gas-powered canopy, and even its own sound system. You know. So your already-rather-unique ride can have it's own sexy soundtrack. [a href="http://www.designboom.com/weblog/cat/8/view/15132/sofa-bike.html">DesignBoom]