Bertho shared his flipdot project in the forum:
For those of you who don’t know flipdots, these are mechanical discs (black/white or black/color) that flip with a (semi-)permanent magnet which can be polarized in either direction. A large current must be applied to a coil to flip the magnetic field and the disc will flip. Flipdots are available in 1×7 strips and in different sizes and colors. The direction of the current through the coil depends on which direction you want to flip. The current must be kept at 350mA for at least 450 micro seconds for the permanent magnet to reverse polarity.
Via the forum.
Check out the video after the break.