I once saw this thing on the news, about the reward money being offered for Saddam. They were asking all these peopel, what would you do with ..sorry I forgot the amount, but like, 5 thousand dollars...and it was so much money to them, and they had lived all their lives without money, the people had no clue. They said stuff like." I would buy more food for my donkey, so he could carry more to market." or "I would buy more seeds, to have more vegetables to sell."
Also, I recently got a bit of money from selling a bit of land. It actually wrecked a couple friendships. If I came across a billion dollars, I would use just enough to get myself out of debt, buy my kids a pony, finish my house...windowsills would be nice...probably build my mom her own "guest house" for when she finaly losses it. I would tell no one, and find ways to secretly help people out.