If I were the richest man in the world, perhaps, I will donate some for charity - it gives me to benefits actually, first, I could escape from those high taxes that the government is imposing. Sponsoring a certain foundation will save me from those annual taxes! Haha! Second, I will feel bliss that I have helped!
Then, bank rolling my money to generate some more income and to keep my first vision possible. Of course, travel the world will never be put aside!