For one of our sponsors, Burd Ford, we did a months worth of demos a few times a week for the opening of a new dealership of theirs.
Thats an extreme case, but usually for sponsors we bring 1 (or more... the more the merrier

) and do a demo for them.
The advertising on the robot of course is the favorite way of doing it, plus a team picture never hurts as others have said.
-q