An automotive xenon bulb, even the mercury is visible being the reason this type was banned. Inside an electrical discharge only a few mm long excites mercury and various salts to create intense white light. Everything is under a lot of pressure and at high temperature

The tip of a diamond glass drill bit, covered in 100s of small industrial diamonds. With water and some pressure at low speed it drills glass by creating tiny cracks eroding the glass.

Shown here the tiny mechanism of an analog Voltmeter. An electromagnet responds to the voltage and is countered by a small coiled up spring, similar to the ones in watches. The lever let's you adjust tension and by that zero.

A CCD image sensor, a technology mostly long superceded but not gone