First off, congrats!
Lots of great advice in this thread that is impossible to beat. But $8M means you can do whatever you want: including nothing. You can do absolutely nothing. Or! change your life. It's up to your personality and how you view money and time. You don't HAVE to work anymore... or you could go work at something that excites you. Or travel the world.
But whatever you do, use it to do some good in this world. Even if that's just being a great father to your kids.