Check it out, it is the best tool for Options trading, free for individual use.

The Options Lab provides dynamic charting and strategy analysis on 56 commonly used options stragtegies. Just enter 'aapl' for Apple, then select a strategy such as butterly to see what the strategy looks like, change the Days and Volatilitys to see how the position evolve over the life of the options

Sample Chart:

http://i31.tinypic.com/281bev5.png

http://i32.tinypic.com/30ucvfm.png