Gentlemen and brutes, you would both do well to study the life of John L. Sullivan, aka The Boston Strong Boy. He was not only the first world heavyweight champ of gloved boxing, but the last bare-knuckle one. He was the first athlete ever to earn one million dollars, which in 2008 dollars is about $23 million or in 2011 dollars, $500,000.
A mighty mick with a prodigious appetite for food, drink and fisticuffs, Sullivan fought over 450 matches in his career by boxing anybody with $500 to lose while killing time between official bouts. He traveled the world in search of something that would accept his gentlemanly punches: The reason there are no more California grizzlies is that they fled when they heard John Sullivan was looking for a fight. And yes, he had a handlebar mustache that could also beat you up.
He lost only once (officially, but there are a couple of hard falls in his world-travelling record). The biggest obstacles to his career were not being allowed to drink during training and the fact that God kept turning down his challenge to fight. He also had a hard time finding venues where it was legal to pound a man into glue: Apparently those laudanum-swilling savages of the 19th Century weren't brutal enough to watch Sullivan scientifically dismantle the human body, so boxing was illegal in most states and countries. One notable example of such a black-market bout was the time he and Englishman Charley Mitchell (who would later become his lifelong friend, as would you if you met the only other thing on Earth that could not die) pounded fists for two hours in the rain, only stopping when the police showed up, having been alerted by the shockwaves from their punches, which were threatening nearby buildings. The police force's arrival coincided nicely with neither man being able to lift his arms anymore because they did not know how to fall, they knew only how to fight. Les gendarmes arrested Mitchell, but Sullivan escaped due to the iron shackles being too scared to go near his fists. He escaped to Liverpool, where he arrived as a mysterious, bandaged figure that had locals wondering who had TPed a mountain.
When he fought Jake Kilrain in the final bare-knuckle title bout, everyone thought Sullivan was finished after he vomited in the 44th round - what they didn't know was that vomiting was just The Boston Strong Boy's way of exorcising anything in his body that wasn't tough enough to defeat him. The mighty man got up and pummeled Kilrain into the 75th round, at which point the latter's manager threw in the towel--although it's possible the towel was just pulled into the slipstream from one of Sullivan's punches.
What did he do upon retiring? Only every job a man could ever succeed with -- actor, public speaker, umpire, sports reporter and bar owner. He lived richly, and died at age 59 with just ten dollars in his pocket, which means he budgeted his fortune perfectly for the end. You might call it a young age to die, but we like to think John Sullivan shortened so many lives, he submitted his timecard early to make up the balance. And damn, did he eat, drink and fight well getting there.