Dinotte Lighing!
I gotta give a HUGE thumbs up for Dinotte as well. (http://www.dinottelighting.com )
I have two of the 200L lights -- one for handlebars and one for helmet, and I'm using the Li-on batteries. I LOVE them, and their customer service is extraordinary. Their lights are available at REI and Nashbar, but if you order directly from them, you get extra batteries and who knows what else they'll throw in. Rob helped me put together the exact package I needed.
For 3 days, I get to part of a thousand other journeys.