I know a guy who has one of these
http://www.angletechcycles.com/notsausage/techass.htm
STP last year, he was the only person I could pick out in the throng of people - all day long. I don't know about night.
I *think* the angletech source is still just the light and you have to go to an auto store or something and get a mount. So, I plan on ordering from Technical Associates when I get around to it.
https://secure.techass.com/el/raven2/raven2.php