Oscar the Robot, Promotional Robot for hire "has the ability to reach, touch and engage with people like no other. Promotional robots can help drive leads, sales and awareness of products and services to both the trade and the public."
Oscar is technically a Mechanical Turk. It moves around a lot and is an excellent and charming conversation starter. It got them some press attention too, but I was most impressed by the way it generated sales leads for the Oracle specialists in their LeWeb booth.