Drug dealing, especially in the inner city. You could find most of the skills he talks about learned by dealing drugs. You want to learn things like Learn Per

Drug dealing, especially in the inner city. You could find most of the skills he talks about learned by dealing drugs. You want to learn things like Learn Persuasion, Attract Luck, Find the Action, Combine Skills, Fail Forward, then look at drug dealing. The only skill that doesn't strongly apply is Write Simply, although it does to an extreme -- in the sense that the less you have written down the better off you are.