Look Ma, No Glue: Electrostatic Adhesion as If by Magic

A vertical PCB surface was holding pieces of paper as though they were pinned to it as on a notice board, yet there was no adhesive or fixings in sight. A PCB with extra insulation has an array of conductors on one side that carry a very high voltage. High enough for electrostatic attraction to secure a piece of paper to the PCB.

Source: hackaday.com