I read a book long ago on blackjack card counting. It's possible to take the winning edge, the maximum bet size, and the number of bets per hour, and figure out what your hourly wage is doing this.

Also figure in this being hard work, as it requires your full attention.

The pay just wasn't that good, and besides, the casinos will ban you when they figure out you're counting.

So that wasn't for me. Instead, I invest in the stock market, where "buy and forget" is not much work, and the odds are much better.