Stumbled upon this item on ebay. Looks cool and way cheaper than the other USB Follow Focus

Dont know how to post pictures here. But this is the link : http://opteka.com/ff1x.aspx

The Opteka FF-1X USB Follow Focus controller allows you to adjust focusing, start/stop video recording, control digital zoom and enable live-view remotely from Canon's built in USB protocol to enhance your HD filmmaking experience. The FF-1X is compatible with the Canon EOS 1D IV, 1D X, 5D MK II, 5D MK III, 7D, 60D, 500D, 550D, 600D, Rebel T1i, T2i & T3i DSLRs.

Features

Controls Focus via Camera’s USB Starts/Stops Video Recording Controls Digital Zoom to Aid Focusing Enables/Disables LiveView Initiates Video Capture Image Powered by two AA batteries (not included)

FF1X mounted to the Opteka CXS-500 Rig (camera & rig not included)

Specifications

Connectivity

USB (uses cable included with camera)

Power Source

2 AA Batteries (not included)

Battery Life

Approx 50 hours

Construction

Aluminum, ABS Plastic

Rig/Tripod Mount

1/4" thread

Dimensions (LxWxH)

2.9 x 2.9 x 2" (73 x 73 x 50mm)

Weight

2.75 oz (75g)