On Fri, 23 May 2008 07:12:26 -0700 (PDT),
wrote:


I regularly see cyclists with flashing rear lights in poor light (well
I did through the winter). They were wasting their batteries as
without exception I could see they were there before I could tell the
light was on. Whatever light you saw must have been pretty bright to
catch your attention in your mirror.

They might not have had batteries - might be Reelights...
http://tinyurl.com/3pmmxg (Wiggle page about Reelights)

Admittedly in daylight Reelights would possibly not attract the
attention of someone not already looking in that general direction

--

John