The Paroli Method: The Paroli System is really sort of an anti-Martingale strategy and is my favorite among the classic progressions. You begin with a one unit bet and you increase your bet by one unit whenever you win rather than when you lose. On any loss you regress back to a one unit bet.
This is not a bad way to play. However, you should have some firm rules as to how large you will let your bets build up on a winning streak before regressing them back down to one unit. This obviously depends on the type of game played and the odds of the bet.
My personal play when betting the Paroli system is to begin with one $5 unit and increase on each win until I reach a $25 level. I take one hit at $25, regress back town to a $10 unit bet, then repeat the process - this time taking it up to $50 before incorporating a second regression.
The advantage of this system is that it can be played with a relatively small bankroll. When you incorporate some self-imposed rules such as I outlined above the strategy forces you to manage your money. You only need to maintain discipline and catch the right streak.