I just got a tiny Firefly Supernova light from RoadID -- they were having a 15% off sale* and I'm a sucker for sales. 
http://www.roadid.com/common/firefly.aspx
I got a red one and it attaches very easily using a thin strip of velcro to the back of my helmet (a Bell Array helmet which I just purchased from TE at 20% off -- I've been needing a new helmet for a while now, and did I mention I'm a sucker for sales?
)
The light fits perfectly and snugly strapped onto the back of my helmet -- I didn't use the little clip provided, I just ran the strip of velcro through the small loops on either side of the light and wrapped the velcro strip through the nearest vents in the back of the helmet. It's tiny and lightweight and I don't even know it's there, and it turns on & off by a simple twist of the cover. It can change from flashing light to solid light by opening the case and flipping the battery, so it's not a change you can make on the fly. I'm going to keep it as a solid light anyhow so no biggie for me.
Anyhow, I've been wanting to have a taillight at head height and this fits the bill nicely.
(*I just checked the terms of the deal -- you have to be a previous Road ID customer, and you have to log in using the email addr you used to place the previous order. So if you're eligible for the discount you've already received an email from RoadID)
Last edited by jobob; 11-22-2009 at 09:39 AM.
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