Train animatronics?

I am just starting to get into lego trains and am formulating a MOC idea for a train with a few moving parts on it for display (think Disneyland animatronics, but on train cars). I would like to do this without introducing additional power units, and in theory could do this with a "motion tap" from the rotation of the wheel axles. But I plan to build this train around articulated two axle wheel trucks at each end, and this would complicated the motion transfer. Can anyone point me to any MOCs...