The ArchRig system is a new rig and follow focus combo unit that looks to somewhat simplify on-the-fly focus adjustments when shooting HDSLR video.
Instead of a geared focus mechanism attached to the side of the lens, a metal arch goes over the top of the lens and use stop-pins to serve as focus marks for the lens lever. Additional focus marks can be made on the arch using a dry-erase marker.
Check out the video below to see how it works.
[youtube http://www.youtube.com/watch?v=rDgrdg8kh5w w=640&h=360]
The ArchRig is available on Amazon.com for around $250.
More details on ArchRig.com.