IF you got lucky you can make some money short term with Martingale , however like everyone else said already - in the long run you will lose. You cannot trick math..
Like someone said early in the thread you cannot really escape from your emotions. However the purpose is to not make a trading decision based on emotions, but rather on objective factors.
You can get many no-deposit bonuses. However usually they are for very small amount $10-30 (********** give up to $100 if I remember correctly) and clearing conditions are terrible. So you end up losing the bonus very fast, but still need to trade a lot before withdrawing anything is possible...
Well both the gambling and trading are zero sum game (in order you to win someone else must lose) and also they are not productive for the society. It doesn't matter how good trader you are - you are not producing anything, just money switch hands in your direction more than the other way.