Billionaires have the money to make things happen. The ultra rich individuals on this list for the most part have two main subjects on their mind: space travel and immortality. Almost all the ideas appear to be for the benefit of mankind.

If you had a spare US$1 billion or US$100 billion, what would you spend your money on? These men could have anything in the world, but they want more as they push the boundaries of health, science and infrastructure.