I created this blend for weekend challenge #548 over at blenderartist.org.
The theme for that week was: Soviet Technology.
After some searching, I discovered that Russian Oleg Losev reported creation of the first LED in 1927.
So I decided to model an LED light. I used Blender 2.69 and rendered in Cycles.
The modeling was not that difficult, but getting the materials to do what I wanted was a struggle that I feel I didn't quite meet. However, I am still somewhat pleased with the final result.
This image is straight out of Blender with minimal compositing, and no additional tweaking with any external image editors.