The hustlers of Dota 2
Back in 2011, Jonathan Belke was a professional gamer. He had modest success with strategy game StarCraft 2, culminating in a 1,000 euro prize at the ESL Pro Series in his native Germany. But while many of Belke's fellow pros struggled for cash, he found a lucrative side career: betting on matches. In February of 2014, he said on Reddit he made five figures in euros, exponentially more than his tournament winnings — though he didn't bet on his own matches.