I think the best way is buying and selling and looking for niches. Really, if someone wanted to really try hard, you could make a lot money right here on this site by trading cash and points around on the various sites. Every week there are several players looking to make VERY FAVORABLE trades, and usually they find no takers. And this is just one example. I am sure you can make enough money to support a poker habit by putting in a couple of hours of work per week this way.