Mini-CCFLs: Size Is Not What Matters
Mini-light sticks are especially well suited for smaller cases. These highly intense, compact 4" (10cm) light sources come in a wide array of colors and are easier to install than the alternative version, 8" (20 cm) longer. A set of two costs about $7.
These small light sticks have a high luminosity
Some fans and motherboards react to UV light
The action radius of UV light is limited
It doesn't get any lower than this - cold light from below
Even in the light of day, the lighting effects are impressive