This is (going to be) version 2.0 of an open hardware motorized pocket dolly that you (a budding videographer who wants access to a high quality but affordable linear motion system) can fit in your trunk and attach to a pair of tripods. It uses a small, portable 12V battery for power.
For linear motion, it uses two rails on a makerslide aluminum extrusion and v-wheels to guide the sled. This version of the Cinemaker Pocket Dolly will (probably) be able to hold up to 10 lbs of video or camera equipment on the sled. The tripod mounts use a universal 1/4"-20 threaded nut that will accommodate the vast majority of tripods out there.
The original 1.0 version is called MakerSlider: http://www.thingiverse.com/thing:33368