Your 4pm board meeting? Better cancel that and, while you're at it, ask for an extension on that looming deadline -- you're about to lose the afternoon to a full-blown HTML 5 recreation of NES classic Super Mario Bros., right within your browser.
An excellent example of the power and flexibility of HTML 5 programming, FullScreenMario.com lets you guide the magic-mushroom addled plumber with either the WASD or arrow keys on your keyboard. Developed by Josh Goldberg, it's the entire game, squeezed into your browser, complete with a random map generator for Mario veterans. Those who'd like to make some Mario levels of their own can grab the source code from GitHub too.
As far as we're aware, this has been put together without Nintendo's blessing, so get your game on right now before the lawyers start throwing their weight around and this disappears for good. [Full Screen Mario]