23. Back to the Future Part II
Set In Year: 2015
Prediction(s): Hoverboards—flying skateboards—are just as possible (and frequently employed) as time travel.
The power to travel through time is cool and all. But by the time this sequel rolled around, we'd already had four years to be impressed by (and argue the feasibility of) Michael J. Fox's 1.21 gigawatt-powered DeLorean/time machine. So his hoverboard became our new object of desire. Though director Robert Zemeckis started a rumor that they were indeed a real thing at the time (the DVD even has a featurette promoting them), it's probably a safe bet that their invention—and subsequent omnipotence—is more than two years away.