I saw a photographer gigging a location last night with some clients. It was dusk, sun was on the horizon and losing intensity quickly... he was using it as a backlight/kicker, but instead of a front-fill flash, he had an assistant using a small hand-held/portable continuous light that he had gelled over. It looked like it even had mini barn doors on it. the entire apparatus didn't appear to be bigger than a large apple.
Any ideas as to what he was using? I'd love to try out the technique!