Even if a good half goes off to taxes, a quarter of a billion would set me up with:
Student loans gone.
Parent's house paid off.
Buy myself a modest house in a neighborhood near my university, so I can finish out school. Rent the property out after I'm done with it.
Buy myself a brand-new car, cash. Nothing fancy. A Focus or something.
Invest in a couple cool Kickstarter programs, mostly indie games and web shows, but also inventions and technological developments.
And after all of that, I'd still have enough to shop local, organic, sustainable, and fair trade everything for the rest of my life, as long as I live modestly.
I'd also buy a plane. Like, a Cessna. Get my license. Fly around to visit family in Cali, Texas, Virginia, Wisconsin, etc.
Oh, and I'd buy an acre of land on Mars. Just so my family has a homestead six generations out when we start colonizing it.