I believe market will go down after fiscal cliff is resolved. However I believe S&P 500 is more safe than Russel 2000. That is why I recommend buying SPY and selling IWM. If you have noticed, IWM has recently outperformed SPY that it should correct itself. Trade equal dollar amount on both sides. In this trade you are hedged and your loss is minimized and your gain is also limited. You should do this trade in high dollar amount to see any profit.