When Eddie Valiant and Baby Herman have an encounter outside Eddie's office, the shadow of the robotic machinery manipulating Herman's cigar can be seen against the bedding in the baby carriage (the animators drew over the mechanism, obscuring it but not the shadow).
The same thing happened with the yellow cab when Roger and Eddie were making their escape (after Roger let the cab out of the Weasels' truck). If you watch the long shots, you can see the guys that were driving the actors about. (I think there were 3, but I know for sure there's one under the 'trunk'. It's been a while since Ive seen the movie, sorry.)