True it adds no social value, but it is arguably the ultimate hacker's game :) You can actually add a little social value by placing only orders that increase

True it adds no social value, but it is arguably the ultimate hacker's game :) You can actually add a little social value by placing only orders that increase liquidity; those where someone else "takes out" your standing offer or bid. That and the fact that your profits are taxed as ordinary income in the US for equities at least.