Awesome Maker "tuckershannon" designed a clock that uses a 405nm wavelength LED to imprint clock numbers on a glow-in-the-dark surface. The mechanical system consists of a five-bar linkage controlled by an Arduino. Attached to the mechanism is a laser that shines over a glow-in-the-dark surface. Whereas the glow fades quickly during the day, at night it shines quite brightly.
At night it's really bright! If you would like to build your own, 3d files, schematic, bills of materials, Arduino code, and links can all be found on my Thingiverse post.