This is similar to a fun trick I used to show people back when CRTs were the predominant television screen. The face of the TV would build up a static charge an

This is similar to a fun trick I used to show people back when CRTs were the predominant television screen. The face of the TV would build up a static charge and collect dust over time. I’d wipe the screen off with a damp paper towel and place it under a alpha/beta/gamma-sensitive Geiger probe. It would hit 500 counts per minute easily(background was about 250). I knew people who took this to an extreme by putting a high-voltage static charge on a needle, then placing the charged needle in a closed bell jar with a pile of thorium-doped lantern mantles. The tip of the needle would pick up enough radon daughters that it made a great rechargeable point source for cloud chamber demonstrations.