I'd probably take some cooking lessons or hire a personal healthy chef, just for a treat. I'd possibly buy some exercise classes, stock up my cupboards/refrigerator with good foods, and spend the rest on clothing and workout supplies.
OOO --- I would get a really fancy treadmill for my apt and spend the rest on sport bras (why are they soo expensive?!?!) and a better pair of running shoes.
I'd make a down payment on a really, really, really good elliptical. It would be sooo great if I could split my hour into two 30 minute sessions and do it at home instead of at the gym.