Scuba,
I think that the goal here is to free your hands and aim the light where you want it.
If you had a specific purpose in mind for this thingy, then I could understand it. Carrying more thingies and widgets just takes up pack space. For the amount of space this thing uses, you could easily carry another light.
To free up my hands and aim light...
I do carry a nite ize headstrap to convert a 2AA or 2x123 light into a headlamp. Takes up very little space, and weighs almost nothing to carry.
For desk use, I have lights that are designed with an anti-roll bezel. (some smaller lights can fit the minimag antiroll device on their bezels.)
I did notice on the same page as the thing, another thingy to mount a light on bike handlebars. Now that I do like!...
But will probably make one. (heh heh - I am cheap /ubbthreads/images/graemlins/icon6.gif )