Wooden knobs.

Using wood in electronics is not new, however I am still fascinated by the idea. Some people may frown and even consider it "ghetto", however the truth is that only the Super Mega Ultra Hi-Fi audio equipment uses them as seen on this website. The knobs can be very nice looking if manufactured and treated correctly. I am not even going guess how much they would sell for on the Hi-Fi tube amp market, because apparently they also contribute to the overall sound making it even more Hi-Fi. To make something like that one needs a lathe and a place to make a huge noisy mess. A word of caution, do not attempt to make these by rigging a handdrill sideways and using a flat-blade screwdriver to shape the wood. One trip the the ER may cost a lot more then getting a mini lathe ( unless you live in a country that has a public health care system ) and all the needed tools online, also please wear goggles.