I would
- do a world travel with my family
- buy a house as well as a new car and some other technical toys
- quit my job and open a business
- give my mom and my elder brother a wad of money
- buy a lot of persons an eBook reader (at least all those who didn't win the MR summer giveaway)
- make a donation (my wife would pick the charity organization)
Maybe i would do/buy some other things but i'm not sure yet what that would be.