I made these as markers for enemy forces in wargames where the enemy is unknown, such as PEFs in Two Hour Wargames products. They look very nice printed in transparent and then given a green wash in the concentric circles to get a "glowing display" look.
Note: I successfully printed this in the older transparent plastic. However, since Shapeways dropped that product, it is now offered in the higher resolution Frosted Detail. I will see about getting this printed in the transparent acrylic, as that migiht be the best material now available for this model.