clairedelune said:
You rock like feldspar. Huge cookie.
OT: Forget buying a private island, I'd build a floating one the size of Crete, which I'd keep in international waters, safe from the rule of all but international maritime law. Then I'd make it a haven for scientists who want to research things no country will let them do, and fund it all by peddling vice. After that was up and running, I'd build self-supporting fortress-compounds all over the world, at least 10 of 'em. Then I'd build a private army to counter right-wing nutjob groups like Blackwater.
Then I'd start buying up huge tracts of land in threatened ecosystems like rainforests and fragile riparian and alpine zones, and around the edges of the Sahara, and use my private soldiers to keep them from being further damaged. I'm sure there's more, but my 4 bils ran out a while ago, so I'll leave you with two final words:
Aerospace Research.
EDIT: I forgot taking down Monsanto. By the time all my various enterprises are up and running, I'm pretty sure I could accomplish that. And EA, the bastards.