Don Donzal, who created www.ethicalhacker.net
and ChicagoCon (link now appears defunct), lists 10 ways for CISSPs to earn CPEs (Continuing Professional Education credits) and having fun doing it. Check out his entire article here. He wrote it in 2005, but it hasn’t aged much.
NOTE: I crossed through some of the links to now-defunct sites….remember, this was written in 2009….