Roger Arquer‘s Bing Bong light needs water to switch on/off. The water works as a conductor between the user and the lamp, undermining our fears of combining electricity with water.

In his Lie Pinocchio Lie, water is again the switcher. When the light bulb is under water, the light turns on. The contilever has two containers, one with the bulb, the other without. When the water is on the long part, the licht is off. When the water goes to the other container and touches the bulb, it switches on.
More electricity + water: Flood Light.

See also Duck Young Kong‘s Saying Without Saying lamp.