Fibonacci: This system is a little more sophisticated, but the results can be as devastating as our old friend Martingale. It is a series of numbers, each of which is the sum of the last two numbers in the system, like this: 1-1-2-3-5-8-13-21-34-55-89-144. Advice about betting it varies, but one of the more common is to bet the series as you lose. If you win a bet, fall back one in the series. If you win that one, start over. If you lose, continue on in the series.