If I've learned one thing from Simone Giertz is that you should make useless things, just for the sake of it (and if you haven't watched her brilliant TED Talk already, you're missing out!). Making this tiara was fun, and it definitely challenged my soldering skills. I was inspired by Becky Stern's neopixel tiara and Jiří Praus' amazing sculptures, and here's the result.
The circuit is extremely simple: it consists of 5 THT LEDs along with 7 SMD LEDs, all in parallel, the base and the oval shapes represent the VCC, while the thin wire from the back is the GND. I've also placed an 18 Ω resistor in series with the LEDs, so the circuit can be powered directly from a 5V source.
I covered each of the SMD LEDs with a drop of hot glue, for robustness (since the tiny pads break very easily) and for diffusing the light.