Recently I picked up a big mantel clock for $5 at a garage sale down the street. The clock uses a hidden pendulum. Like any mechanical clock, with much fiddling it can be made to keep reasonably accurate time, but that's not good enough for my wife.
It occurred to me that some form of electromagnet pulse could be used to sync the pendulum (with magnet attached) to keep it running at the right speed. Might be a fun project. Anybody have any knowledge or experience in this area?