Commercial artist and award-winning jazz bandleader. His day job is drummer for the Rolling Stones.
There's Michael Moorcock. There's a legend told about him, not quite factual.
Moorcock is most famous for writing the Eternal Champion series of fantasy / science fiction novels and stories, most notably the hugely popular ones about Elric, the spooky albino warrior with his spooky magic sword Stormbringer.
In the 1960s Moorcock was publishing New Worlds magazine, which lost money every issue. But guys like Harlan Ellison, Norman Spinrad, and J. G. Ballard were busily reïnventing science fiction in its pages. Mr Moorcock didn't want to change the magazine and he didn't want to let it to go under. So every so often, the magazine would go broke and Moorcock would retreat into a room with a typewriter, a ream of paper, and a lot of amphetamines. Three days later he would emerge with enough Elric to keep the magazine afloat for a while longer.
Then there's my man Steven Soderbergh.
His avocation is directing gutsy, experimental, flawed, ideosyncratic films like Kafka, Bubble, Full Frontal, and The Limey. (OK, The Limey isn't flawed, it's perfect.) Or my favourite example, spending a fifty million bucks of other people's money to do a remake of Russian master filmmaker Andrei Tarkovsky's long, slow, brilliant philosophical science fiction film Solaris.
And then, when he runs out of money for these things, he just rounds up a bushel basket of the biggest stars in Hollywood and cranks out another one of these.