I learned this week that planning poker is a big return for the small investment. I could not find planning poker cards in stock anywhere in the world, until Mike Cohn just made them available again (http://www.mountaingoatsoftware.com/products/cards).
Besides all the great benefits outlined in Mike's great book on Agile Planning and Estimation, I found that the team interaction was good. There were great alternative views and just an overall good feeling of everybody's opinion counting.
