A conservative estimate on the number of "problem" or compulsive gamblers in North America is around 1% of the population (between 3 million and 4 million people), but some say that number may now be as high as 7% -- up to 28 million men and women. Online gambling poses a unique risk because of how available it is. You sit back in your recliner wearing your PJs, turn on your computer, and -- bingo! -- you've got 24/7 to lose your savings account. As online gambling sites have increased in number from 15 in 1995 to more than 2,300 in 2010, so have revenues. The people who run the games took in $24 billion in one year. That's how much is being lost.