The Aztecs were more fond of human sacrifice than the Mayans, but I did get a kick out of the hordes of tourists at Chichen Itza posing with the chac mool, not knowing what it was used for. I resisted the urge to walk up to a group of smiling tourists and say, "By the way, that's where the heart of the human sacrifice is placed after it's taken out of the body by the high priest."
I think the Aztecs and Mayans both lifted the chac mool from the Toltecs.