Nikon Charger MH-62
Charger for Nikon Coolpix camera that slowed down until eventually one day it just stopped working. This charger probably still works. It’s the need for the charger that has become obsolete. The battery that the Coolpix used was the proprietary EN-EL8 Lithium Ion battery. It strikes me that anything in the tech world that is proprietary is doomed for obsolescence as soon as it hits the market. Unlike the nice and generic charger for the Realistic Minisette tape player, which worked with many objects of its era.
Status: The sea monster has laid claim to this as well. She needs juice too.