Having made up his mind to be at the cutting edge of eighteenth century art, 13-year-old Joseph Mallord William Turner stuck his pictures in the windows of his dad's London barber's shop then sold them to customers (who thought they were a snip). Joseph's mum had died when he was little so his hairdressing, wig-making pop made himself responsible for his upbringing and taught him to read and write, but left his artistic training to the Royal Academy. Joseph's diligence, artistic abilities, progress (and hairdos) were remarkable.
At 15, when most lads of his age were doing normal stuff like hanging around the pie shop and nicking sedan chairs, Joseph was busy making his first submission to the RA Summer Exhibition… and getting it accepted. By the time he was 20, this over-achieving artaholic had his own studio and a long queue of printmakers waiting to reproduce his originals. Which just goes to show, give a child a ludicrously important and pompous sounding name and they'll do their best to live up to it.
Joseph spent the rest of his career whizzing around Europe, getting off on atmosphere, light and all manner of natural phenomena and consequently producing some of the most brilliant and radical art of his time. However, possibly as a result of a life spent creating some 19,000 paintings and drawings, he began to show more and more 'artistic' tendencies, including bidding for his own pictures at auction, refusing to sell to clients and sulking for weeks if anyone did persuade him to part with a piccy.
After spending his final year living incognito (a suburb of Chelsea) under the alias Admiral Puggy Booth, Joseph died leaving a fortune, having expressed a wish for it be used to support 'decaying' artists (or Damien Hirst, as he's now known).