Shooting photographic portraits is the market that most photographers, whether amateur or professional, start earning money with their camera. That"s where I started many years ago before I began submitting to the Microstock Photography.
The game of poker is the one that is easiest to identify with gambling. Unlike in the case of the slot machines, you do not need to take yourself to a casino if you want to play a game of poker. All you have to do is call some of your poker-playing friends over and sit down with a few mugs of beer and a decent amount of money to throw away.