A few years ago my mother gave us this Cool Circuits puzzle:
If I chain together the individual links into a complete circuit, a small fanfare of lights and sounds is produced. That is, it used to work that way. Moths and rust have had their way with the internals. There are metal wires running through each link, and I think a complete circuit is detected using electrical induction—though I can’t tell exactly where things are going wrong. But who cares. The player can tell when the circuit is complete just by looking at it. The electricity may not flow, but the dopamine still does.
Ever since we received the gift, I’ve been very concerned that we’d lose one of the links. Few things are more tragic than an incomplete puzzle. To put my fears to rest, I have finally archived the pieces in a Madeup program, which works by wrapping arcs around circular nodes on the puzzle’s grid: