After reading all this, if anyone is really truly interested in exploring the whole idea of becoming a professional gambler, they should check a book called "How to make $100,000 a year gambling for a living" by David Sklansky and Mason Malmuth. The real key is to only play games where skillful play can result in a player advantage. The long and short of it is that games like: poker, blackjack (using card counting and a favorable situation--such as single deck games), sports betting and special promotions (such as internet casino bonuses). Then of course, you need to know how to manage money because even if you are playing "beatable" games as described above, your results can still vary tremendously (statistically speaking). Also, if you think about it, in poker you are not playing against the house--you simply need to be a better player than your competition! I lived in Vegas for 7 years and the most successful people I knew were poker players. This should tell us something. With sports betting, the whole world has changed in recent years. You can still get online at offshore sportsbooks (even with that stupid law Bush signed earlier)...and by the way, technically speaking internet gambling for US citizens is NOT and has NOT been made illegal. What the law did was make it illegal for the casino's (and their banks) to accept the money specifically for the purpose of gambling. You can still find ways around these regulations.
Yes, sportsbooks. There are so many different ways to bet sports now that the traditional pointspread betting has to a large degree gone out the window. Just look at some offshore books and see the vast array of teasers (where you can actually move the spread in 2+ games...you do have to win both to win money, though), point buying opportunities, totals wagering, etc.... Sportsbooks will run promotions and advertise bets that they know they can be beaten at! Before the boards jumps all over me for saying this, understand that this is MARKETING. They know that most players will come on board, trying out their latest gimmick. Maybe they have some early success. However, then they start playing other games (maybe in the casino) or making other sports wagers that they not have the knowledge to bet profitably. This has the effect of eating away all their initial profits and maybe even giving back most of their original stake.
I know this post has been rambling a bit, but I hope I have given some useful information. Bottom line is that I think (heck, I KNOW) it's possible to be successful at gambling, but it requires focusing on beatable games, and a large amount of discipline, self-control, and excellent money management (as well as a solid bankroll going in to weather short-term fluctuations).