When we have visitors, I like to give them a little something after we sing the welcome song. It isn't anything fancy, just a little musical memento.
I have done this two ways. Sometimes I have given the kazoo to the visitor only, and other times I have invited the person with whom they are visiting with to come up as well when we sing and they get one too. The second way helps promote inviting their friends to Primary!
The little kazoos I bought from Oriental Trading here.