Here is a motorized marble run that puts on a mesmerizing show on your desk as you let it run. This AmazingWood Kinetic Marble Run uses a DC motor for the lifting mechanism. It has 2 lifting mechanisms in two levels that raise the marbles to the top. Once there, the marbles move through the ramps and reach the bottom.
This marble run measures 10 x 7 x 8″. It uses 3 x AAA batteries.