In addition to the MK trash can, the other one is at Rafiki's Planet Watch (conservation station) at Animal Kingdom. We saw it back in September, and it was a real hoot.
We shamelessly sent our then 18 mo son over with a plastic water bottle to throw away. The trash can spun around to present the proper side for recycled materials and told him "you can put that in here." After he tossed in the bottle, the can responded with "Thank you! Good job!!!"
It was also harassing many of the passers-by, asking one guest wearing a grass skirt for a "hula demonstration", and frequently making "ahhhhhhh" sounds as small children peeked through the lid looking for someone inside the can.