I just stumbled upon the work of Tim Knowles, whose art explores the mostly hidden, obscured, or otherwise unnoticed motion of objects. One of his projects is Tree Drawings:
Drawings produced by pens attached to the tips of tree branches, as the branches move in the wind the tree draws on to a panel or drawing board on an easel. Like signatures the trees drawings tell of the tree's character; a Hawthorn producing a stiff, scratchy & spikey drawing an Oak a more elegant flowing line.
Here's the oak at its easel and the resulting art:
For Vehicle Motion Drawings, he constructed an apparatus to capture the motion of a car being driven...the turns, stops, and starts of the vehicle move the pen over the paper. His postal projects capture the motion of packages through the postal system, both with drawings and photography. (Knowles' Spy Box reminds me of Kyle Van Horn's cameramail.)
Love his stuff. (via waxy)