[Ivan] likes to take time lapse videos. Using his 3D printer and a stepper motor he fashioned a rig that allows him to control the camera moving any direction on a smooth floor.
The dolly has a tripod-compatible mounting plate and scooter wheels. An Arduino runs the thing and a cell phone battery provides power. A pot sets the speed and [Ivan] provides code for both a linear pot, which he suggests, and for a logarithmic pot, which he had on hand. You can see a video of the results below.
The device looks good thanks to the 3D printed body; [Ivan] provides the STL files if you want to reproduce his work. You have to print several of the parts multiple times.