Michael Bloomberg is my sort of billionaire. He put himself through university, built a media empire from scratch, made the city of New York more liveable and has an age-appropriate girlfriend.
Yet after touring the new Bloomberg headquarters in London that he opened last Tuesday, I can see he may also be remembered for something more humble: toilets. Or rather, the amount of water needed to flush a toilet.
This is because Mr Bloomberg likes to spend his spare cash on earthly problems such as climate change, not wacky treks to outer space and other pet billionaire pursuits. So when he hired the British starchitect Norman Foster to design his office, he said he wanted a showcase for the greenest, most environmentally-friendly building possible. That is pretty much what he has got, at a reported cost of £1bn.