What's the smallest flashlight by Arc and how does it compare in brightness with a Modamag Draco (Q4-Q5)?
It uses a single AAA cell and has less output since it doesn't overdrive the LED (only around 300-450 ma on high), but it will have very good runtime on all levels.
About overdriving the LEDs, doesn't the Cree XRE have a within-the-specifications current of 350-1000mA?