Pay off all my debts and debts of my friends/family members (close friends and family members, not like friends of friends or really distant cousins). Anyone who has car payments, house payments, etc, would get taken care of. I have a pretty small circle of people I consider close friends. One of them is currently working at a job he hates because of debt. I'd take care of that, then I'd accompany him just for teh lulz when he goes to tell his employer exactly what to stick and where to stick it.
I have no kids of my own but do have a niece and nephew, and I'd set up a trust fund or something to cover their college expenses.
Get a CPA/financial advisor of some sort (I actually know a few I can trust) to help me manage the rest and get the most out of it.
Live comfortably for a very long time (if not the rest of my life). That's a shitload of money, and I'm pretty sure I'd be able to stretch it for a good while as long as I'm not blowing it on stupid "I have way too much money and want to throw it around" shit like Ferrari collections. I like to think I'd continue living the same way I am now, but I'd have all my debts paid off and no longer need to worry about money when unexpected costs like car repairs, medical expenses, etc, come up. So there'd be no financial stress, which would be cool.
Oh: and build the most badass gaming rig that money can buy.