Any bike can give you a good workout, but almost all of the effort comes from your legs with very little input from your upper body. The RaXibo is designed to spread out the load, but letting your arms get in on the action.
The Swiss made RaXibo puts a pair of hand cranks up where the handlebars would normally be, and the rider can crank away as they pedal, bringing a whole new set of muscles into your riding workout.
Just how you can pedal with your hands without jerking the bike's steering violently from side to side isn't clear, but the rider in the video doesn't seem to be having much trouble. I'm a little less convinced about the efficiency of the contraption, as the upright riding position seems like it would rob power from your legs, while increasing wind resistance.
The RaXibo Hand-Tret-Velo comes in two versions, the basic setup with 26-inch wheels for around $2,600, and the Special with a larger 29-inch rear wheel for about $2,900.