Turns out the plug that attaches to a MacBook power brick is called a "duck head", at least in the Netherlands. I had just bought one at Apple Amsterdam (the "iHostage" movie location😬) and went on a walk in nearby Vondelpark … when these little guys recognized a kindred spirit…
@danwood I was just introduced to a pair of ā€œduck billā€ pliers which belonged to my grandfather.