rock, paper, scissors has exactly a 50% payoff (although it may use some strategy to beat people who think rock always wins)

You can try using Martingale http://en.wikipedia.org/wiki/Martingale_(betting_system)

ie. bet 25 flezz, if you lose double it so if you subsequently win you get your initial cash back.

This way, you have to lose 5 times in a row before you are too far gone to recoup in one bet (25,50,100,250,500). Chances of this are (0.5 * 0.5 * 0.5 * 0.5 * 0.5) = 1/32, which feels kinda high to me. (payoff after 31 bets at 25 apiece is only 775, not enough to cover losing 500+250+100+50+25)

If you start on 5 bucks, your chance of losing money drop to 1/128, but you’ll be playing all year to actually make money.