This is a remix of Rainlight_and_Diffuser.stl used in the awesome OpenRC F1 car - 1:10 RC Car project. In the original version the rainlight is fake, but I wanted to have a working one, so I edited the Rainlight_and_Diffuser part slightly. I used two LED's from this light strip (1m 144 IP30 version) and connected them to this tiny arduino pro mini, I used a 5V version to be able to use the power provided by the receiver. The arduino code to control the LED's are also provided for download. In general you could use different solutions for the rainlight, you don't really need an Arduino here, I decided to use an Arduino and the light strip because it's using the very bright and multi-color WS2812B led's, to be able to add more functionality later, for example different colors or blink frequencies when the car's lipo is running low.
You should print the Rainlight_Glass.stl in transparent filament of cause ;)