Image from TradersMagazine.com
Coming from a futures background, I've never sought after the hand signals used on the CBOE and AMEX but upon suggestions, I agree they're a worthy addition. It'll be a while before I can incorporate them into the gallery at tradingpithistory.com but in the meanwhile here is a link to a thestreet.com article and some video clips (in Real player format which is required to view them):
Easy Money: A Look at the Hand Signals Used at the Amex