This light is made for Kindle version 4 (not the touch version).
The light come from a green LED, powered by the Kindle using the two small pads on the back on the kindle (I think those two pads were here to power a light built-in a cover ?).
Anyway, the two pads behind the Kindle can deliver 4V-4.1V.
My green LED works with approximatly 2.4Volts and 20mA current.
So I had to add a 100ohms resistor.
I added four magnets for the connexion between the LED and the Kindle, to allow me to remove the LED (for transport, and because it's funny).
I put some tracing paper in front of the LED to dim the lighting. I will maybe add another layer of that paper to dim it more.
At the beginning I designed a printed foot for the LED, but finally some stell wire (0.6mm diameter) is enough and allow me to bend the light wherever I want.
Video : https://youtu.be/UfkJRB5TEB0
I used the spiral printing method (the vase mode), so it has only one perimeter.
Since I used that vase mode, it removed the hole for the LED, so I had to drill it after.