Instructable: https://www.instructables.com/id/Coloring-Lamp/

I made a lamp as a tool to help people experiment with additive color theory. Although the lamp is able to display R, G, and B colors at a variance, it could be further improved through tinkering with mapping the colors so that the maximum brightness of all three LEDs could be the same. Currently, the blue LED is the brightest and overpowers the other two while red is the dimmest.

Here is a video of the final lamp: