Laithorn asked if I’d put up schematics for my LED fox ears. Here goes! It’s a bunch of Adafruit Flora Pixels hot glued to a black plastic headband I found in a dollar shop. I wired them directly up to a Digispark (tiny arduino thing) which is powered from a 9v battery in my pocket. Flora Pixels need only one data wire, so you can power them through regular stereo audio cables which are strong, plentiful, comfortable and asthetic, and you can use audio splitters to hook multiple things up in parallel. I used 3mm high brightness side glow fiber optic cable to light up the edges - it plugs straight in to the little kandi bead sockets and lights up very brightly. Squirt a little hot melt glue in the socket to hold the fibre in there perminantly when you’re done making the ears, and use clear fishing line and a blanket stitch to stitch the fiber along the edge where the white polar flece lining meets the ear fur. Put lots of harsh bends in to the fiber to make it hold the shape you’re after - it doesn’t hurt it or make it leak light unevenly.
The arduino code for digispark is available here. It should work on other kinds of arduinos too. The push button cycles through the available animations. To turn it off unplug the battery. Make sure to get a fairly stiff headband because most aren’t stiff enough to hold the weight of ears.
Edit: Oops! Data should connect to pin 1, not pin 2! Fixed now