Is there any style of light tripod (or monopod even), past or present, that can be opened/closed one handed, switchblade knife/automatic umbrella style (eg via a compressible spring in the legs and a central release mechanism)? Only thing I could find is the "producttank" prototype...
I have an old "SLIK" monopod that has a release button and spring that will deploy the top section (1 of 4) about 5 inches. It even has a warning label to point it toward the ground. It's a fairly powerful spring, powerful enough that if you let it freely deploy it would probably break itself after a few dozen uses.
It's intended to be a convenient fine height adjustment, like a tripod center post, without having to mess with the leg segments. The spring is powerful enough to support an SLR and moderate telephoto lens without collapsing.
I've used it mostly in crowded seating like stadiums and such. It's light enough to carry without the groaning of committing to a full tripod, but of course not nearly as useful as a tripod.