For night cycling visibility, I'm thinking the best combination of
eye-catching and low-hassle would be a glowing "strip" around the edge
of my helmet, say 2cm wide (in addition to the mandatory bike lights
and reflectors). Sure, it's probably also the daggiest option, but
let's ignore that for now...

This would be visible from all angles, at most drivers' eye level over
bonnets and through car windows. What do you ppl reckon? Does
something like this exist? The closest I can find:

http://shopping.rednova.com/catalog/...Nite_Dawg.html
Only problems are it's designed for a dog :-), not quite long enough to
go around the helmet, and a tad heavy at about 500g, being a heavy duty
collar...

http://www.theledlight.com/LED-Tailight.html
http://lib1.store.vip.sc5.yahoo.com/...l-03-10-lg.jpg
A thin band, but otherwise looks good!

REI has both of these - I've ordered from them once before, no probs.
http://www.rei.com/online/store/Sear...=-1&catalogId=
40000008000&brandQuery=Nite+Ize&showPictures=1&