$US60 for a bent piece of stainless steel it may be, but DSLR shooters will go crazy for this. It lets you control various focal subjects, by setting and remembering their focal points using just a few markers.
Watch the video above to see some examples of Aric Spence’s Follow Focus design, and if you like what you see, you can buy it for any lens that varies between 2.95 – 3.1 inches in diameter, for $US60. [DSLR Solutions via Planet5D via Photoxels]