The Stair-Rover started as a design concept by PoChih Lai, who wanted a want to ride through the city like a surfboard would through water. A skateboard that could ride easily down stairs and the uneven terrain of a city street.   The design was created in 2012-2013, but I am just discovering now. It's an amazing design and one that should come back to mainstream. Check out the Kickstarter from 2013 or the Amazon reviews (though currently sold out).