Randall Munroe's webcomic xkcd has been around for well over a decade, touching on everything from pop culture to science, love, and beyond, and it's garnered a pretty huge audience. To celebrate the launch of his new book, Thing Explainer, Randall Munroe has released Hoverboard, a very simple little platformer where you gather coins from a small playfield and drop them in a box. The end!... or is it?! Using the [WASD] or [arrow] keys to move and jump, you'll find your hoverboard can jump an infinite number of times and take you beyond the designated play area to explore a surprisingly huge black and white world with secrets aplenty. There's not much to do other than take in the sights and collect more coins, but with so much to find, all rendered in a simple but lovely black-and-white stickman style, Hoverboard is worth a romp as a great piece of interactive art full of secrets and references to everything under the sun.