A welcoming gesture originated by one Isaac Washington, bartender on the Love Boat. The gesture: simultaneously pointing both hands in a gun configuration while giving a toothy smile and a sharp side to side wag of the head. Modern variations include the addition of a wink or a cluck, or orienting the gesture to the side.
He was liked by everyone instantly. At first it was his leisure suit that attracted but he sealed the deal givin' each and every person in the room a good, healthy Isaac.