A Verge editor recounts how his partner's joke about buying a motion-activated neon "On Air" sign for their cats' litter box turned out to be entirely serious, resulting in the sign illuminating whenever their cats Noodle or Loaf use the toilet. The idea grew out of a motion sensor originally supplied with the cats' water fountain, which activates the pump only when the cats approach to drink, and the fountain's spare sensor was repurposed to trigger the sign instead.

The setup uses a cheap USB-powered motion sensor similar to the one that already ran the water fountain, paired with a neon sign bought on Etsy (though similar versions are widely available on Amazon). The author warns that poor sensor placement can cause false triggers, and their own sign creates an annoying reflection on the television, though the cats themselves seem unbothered by the added attention during litter box visits.