Yeah, if you want a zillion dollars then buy the sun. See, without the sun everyone would die, so if you buy it then everyone has to pay you for light and heat provided by the sun.

Basically, if you want to grow food or sun bathe, you would need to buy sun license, kind of like a tv license. So yeah, you will get lots of money.

You could also buy the moon, or large parts of it.

P.S. So what your million dollar idear?