Their are plenty downside gaps noted in the chart above as targets below the 78.6 Fib retracement from the March 2009 lows to the March 2011 highs.
For long term investors, coal is highly likely to make a strong comeback, but not likely to start just yet. As downside gaps are filled in this , these are areas to consider scaling in to stocks such as ANR , BTU , ACI , etc. But even then, make sure your time frame is very long term. I would prefer to see positive divergences on a weekly chart (lower prices with strengthening momentum as measured by before getting .
Selling out of the money puts at least 3 months out is a way to capture strong premium and back into coal stock's that you do want to hold longer term. Again, pick your spots carefully if you must wade in this sector.