Quote from momoneythansens:
Most scanners are cheap...but that is a relative term.
If you are an Interactive Brokers client, their Market Scanner has a filter for "Hot by Opt Volume". The scanner is "free" with an account (min monthly account fees apply)
you don't need to be an IB client to get this
http://www.interactivebrokers.com/optionsCommentary/index.php?ib_entity=llc