Wow, I read some pretty good ones. Here's what I would do:

1.) Pay off my brother's hospital bills, and any other sort of financial distress my family would go/is going through.

2.) Finish renovating my parent's house that they've been working on, FOR LIKE FOREVER!!! (It's a never-ending project for them...)

3.) Pay Tim Schafer enough money so he would create another Psychonauts game.

4.) Pay J.J. Abrams enough money to tell me exactly what the HELL is going on with "Lost". The show is called that for a reason...

5.) Find some random people on the street who are down on thier luck and give them some cash, and tell them to remember the kindness that I shown them and to pass on the same sort of kindness to someone else. Totally like what they did in the movie "Pay It Forward".