It's been a couple decades since Marty McFly first went back to the future, and we're still no closer to a working DeLorean time machine. However, one company has created a real-life version of the 'hoverboard' from 1989's Back To The Future Part II, sort of.
A company called Hendo (via Autoblog) has built a prototype hoverboard that levitates a few inches off a surface using magnetic fields. It's a little bulkier than the one first glimpsed on the big screen, and only works on smooth metallic surfaces but, you know, baby steps.
The device's inventor, Greg Henderson, calls it the "Model T" of hoverboards, although that's a bit of a misnomer. This board may represent an early, basic version of the technology, but it's nowhere near ready for mass production.
Henderson envisions using magnetic-levitation technology on a much larger scale, including using it to move buildings and other large objects. It may also have automotive applications, but don't put aside a down payment on a hover car just yet.
The hoverboard's magnetic propulsion is similar in concept to the "mag-lev" technology that was once viewed by many as the future of rail travel. Actually putting it to practical use proved difficult because of the cost of building dedicated magnetic tracks.
Similarly, laying down a network of metal roads probably wouldn't be easy, and since cars rely on friction with the road for control, driving a hover vehicle would be a completely different experience—cars would have to rely on something other than grip to stay pointed in the right direction.
For now, Hendo is running a Kickstarter campaign that includes opportunities to purchase a hoverboard for $10,000, and developer kits to allow tinkerers to adapt its technology for other uses.