A very quick hack as julpyssel.
- Get a few battery powered festive leds in Akihabara
- Measure current and find it was low enough to be driven by a gpio
- Ad a arduino from the project.
- PWM on a few ports.
see more at https://simonsso.github.io/christmas_lights/
Rust version of the software https://github.com/simonsso/rust_christmas_lights