It's not often that I recommend a newly published book here at the Paleo-Future blog. However, Where's My Jetpack? by Daniel H. Wilson is essential reading for anyone interested in paleo-futurism. You can listen to an interview with Wilson here. Below is an excerpt about hoverboards.
Wide-eyed children of the eighties watched in astonishment as Michael J. Fox (a.k.a. Marty McFly) shredded pavement on a hovering skateboard in Back to the Future: Part II. The hoveboard was just like a skateboard, but with one crucial difference: no wheels. His pink and teal board had "magnetic" pads on the bottom and with a quick push-off could silently cruise over grass, pavement, and even water. While this highly desirable piece of movie technology seems very plausible, it crushingly remains fiction. I think I speak for all of us when I say, "Thank you for breaking my heart, Michael J. Fox."
Before you Mythbusters nerds begin crying foul let me emphasize that Wilson does go on to explain that hoverboards do (sort of) exist. Pick up the book. You won't be sorry.