The problem is that such a coat hook with a built-in camera can be installed unnoticed. That's why it's always worth being alert, especially in public places. If you notice such a hanger ...

The foam should be tall enough to conceal the bent portion of your hanger, leaving just the hook sticking up from the top. Fasten your hanger to the blocks by tying pipe cleaners all the way ...

Salmons "The penny and the coathanger" TPT15(1), 46 (Jan 1977) A variation, in which the coin is balanced on the long edge of an undistorted hanger, is described by Sutton M-155 and Miller p63 ...

A steel spring, a 100g mass hanger, 12, 100g masses, a retort stand, a boss and clamp, a clamp, a metre rule, an s-hook, a pointer, safety goggles, a slotted base.