Volvo takes a moment on April Fools' Day 2013 to poke fun at its obsession with safety with the "announcement" of the External Vehicle Protection (EnVeloP) system. When the system detects that a collision is imminent and unavoidable, a full-vehicle external airbag is deployed from the roof, encasing the car is a cushion of air and minimizing damage. Volvo's fake release mentions that the system even deploys when coming in contact with water, leading me to believe that it floats, too.
The EnVeloP is rather extreme and a bit goofy, but Volvo really does offer an external pedestrian safety airbag on the 2013 V40. Perhaps today's April Fools' will be tomorrow's reality.