This is a light-up Rupee. It is printed in clear ABS (though white would work as well) and covers an LED. Use any color LED that you want, or use a Tri-Color LED like I did and create any color imaginable!!!
I built mine with an Arduino Uno and a simple program to cycle through colors and intensity by Infrared Remote Control (stolen from my car stereo). The possibilities are endless.
Please note that the photos don't really do it justice. It is very bright and the colors show a lot better than depicted.
Printed on a Replicator 2X in Clear ABS. The model is all skins, so no infill is necessary. Also, the STL has a large pad to improve adhesion to the build plate. Once it has printed, use a hobby knife to cut it away.