What did you do with your college acceptance letters that you no doubt received at the tardy age of 18? Frame them? How utterly terrestrial of you. 16-year-old Erin King, answering the challenge to "hack" the cardboard tube that MIT sealed her Early Action admission letter in, sent it to near-space on a balloon, thus proving that all those model rockets I built with my dad when I was little were essentially kits for people MIT would consider "challenged."
Update: Erin King, for anyone who hasn't seen her correction in the comments, is actually 17, which, since age is just a number anyway, doesn't at all change how awesomely smart she is. Erin, please — I'm dying for a Mars mission and I think you're the one who can make it happen (no pressure or anything).