Stair Rover Is the Next Awesome Toy Your Teenagers Will Demand [VIDEO]

I just stumbled upon this today. It's a skate board (looks like it could be a long board) that slides effortlessly down stairs! I'm not a mechanical engineer but it looks to me like the board has eight wheels -- four on each side -- and as the board goes down the stairs the wheels alternate so there's always a pair on the ground creating a smooth ride.