Here is a beam shot of a cheap knock off 2AA plastic, ulgy, yellow, (did I say cheap?) headlamp. It is patterned after the Rayovac kids adventure headlamp that is found at wal mart.
Installed inside is the lambda circut in stick formation coil beside the IC and a luxeon star mounted on a 1/8 piece of steel washer trimmed to just fit into the body of the light. the circutboard is expoxied to the back of the heatsink and the star stock aluminum board is connected to the steel with artic silver epoxy.
As of this writing it has been running fully enclosed in watertight plastic housing with 1/4 dead alkalines running full blast for 1 hour 35 min. and the heat regulation circutry has not kicked in yet. the plastic case is warm but nowhere near melting point.
More updates as things progress...