Independently wealthy? If you haven't seen the film, "The World's Fastest Indian" go out today and get it. In 1963, New Zealander Burt Monro traveled half way around the world, on a shoestring budget, to set a world speed record at Bonneville Salt Flats. He did that with no sponsorship, on a 1920 Indian Scout that he had purchased new and spent 42 years modifying. And, at the time he set his first land speed record, he was a 67 year old grandfather. After he began to make a name for himself, he started getting offers of corporate sponsorship, all of which he turned down because he wouldn't let anyone else touch his bike.
What I'm talking about doing rather sounds like a walk in the park, compared to what he did.