The Revo Quad Skate Tabletop Dolly & Articulating Arm Kit
includes a 4-wheel tabletop dolly and an articulating arm that'll let you mount a camera on the dolly in various pan/tilt positions. The dolly supports up to three articulating arms so you can also mount lights, monitors, mics, and other accessories. You can also mount a camera to an optional ball head and attach the ball head to a removable 1/4" screw included with the dolly.
The dolly supports up to 25 lb of gear and can be used on a tabletop or any other flat surface. It moves fluidly in straight lines, curved lines, and wide circles, according to how you align its wheels along scale marks by each wheel. The scale marks are usefully located on the top surface of the dolly instead of the underside, enabling you to align the wheels without flipping the dolly and all attached equipment over.
The articulating arm features a single knob that tightens the center axis and the end joints all into position at once. The arm has a 1/4" screw on each end and comes with a shoe mount that can be screwed to either end.