I saw this light setup a little while ago, just after my HID stopped working. I figured I could cobble something together that would be similarly shaped and sized. I ordered my Cree Q5 WG LEDs on stars, Ledil lenses and bFlex driver from Cutter in Australia. I was going to duplicate Allen's setup, but decided to go with 4 LEDs at the last second. This necessitated a change to the design, but it worked out okay [so far].
The light body is constructed of 1" square aluminum tubing with 1/16" wall thickness. It utilizes plenty of JB Weld, so I hope you'll excuse the crudeness. If I had access to a machine shop and a TIG welder, it would have been really purdy. I have a piece of clear plastic across the back, but I may substitute some aluminum plate.
You can also see the switch and mounting system in this photo:
I used a momentary toggle with a rubber boot to give some grip and make it a bit more weatherproof. The mounting system is a handlebar mount from an old Planet Bike blinkie combined with a hacksawed chunk of said blinkie bolted to the light itself.
On the bike:
The beam pattern is the result of two tight spot lenses plus two narrow floods. It's more of an even pattern than my old Trailtech HID, with less of a hotspot. [Yes, I'll clean up my basement.]
It's being driven at 750 mA. At that level, I should be producing almost 600 lumen. I left it turned on for 15 minutes and it got pretty warm - not too hot to handle, but probably warmer than I'd like. That said, this light is designed for commuting, and the air temp will probably be in the neighborhood of 5C or less.
I'll add some nighttime pics - after it gets dark.
Edit: It's dark now...
The street in front of my house without the light:
Lights on [sorry for the blurriness - 1s exposure and no tripod]:
The back yard:
A garage? Who knew?