6.  Prank Bill and Melinda Gates with 4.5 billion Dominos cheese pizzas

5.  Give every man, woman, and child in the developing world an opportunity to beat that Candy Crush level again

4.  Fund remedial math education for journalists who mess up on orders of magnitude

3.  Buy Damien Hirst and suspend him in a glass tank of formaldehyde

2.  Replace buses with self-driving cars, mail carriers with drones, teachers with MOOCs, and policemen with Soylent

1.  Bury all the money deep into the ground and employ everyone in America to dig it back up again