All: Red or Amber LED blinkie or winkie lights for bikes, typically running on 2xAAA's now, make great $3CND emergency marker lights. Good ones have a clothing clip on the back. They can be clipped to bungie cords, to the front or back of reflective traffic vests (White Scotchlite reflective tape is visible for greater distances than anything else), but they do not stand up well on bare pavement; clipping them to the edge of a gear bag, toolbox or weighted cardboard box works well. They are not daylight visible, but they cannot start a fire either....
Here's an image:
http://www.mec.ca/Products/product_...older_id=2534374302692895&bmUID=1163957399942
North of 60 a lot of dogs have them on their collars as walk lights, and cyclists use the amber ones on their mittens as turn-signal markers. Combined with 2m/yds of white Scotchlite reflective tape tied or sewn into a loop to wear over your shoulder, and you are about set for visibility in total darkness for about $10CND.
For really cold weather, below -20C/-10F, the 2xAA size winkies will last longer due to the greater mass of their battteries, which take longer to freeze. The trend though, is to go to 2xAAA lights so these won't be around for much longer...
http://www.mec.ca/Products/product_...older_id=2534374302692895&bmUID=1163957399939
A good deal is to buy a 2xAA white winkie, which also makes a pretty good cheap LED flashlite in steady on mode, and a red winkie, sold as bike light kits:
http://www.mec.ca/Products/product_...older_id=2534374302692895&bmUID=1163957365504
Put a couple of stout rubber bands on the white winkie with a loop of cloth elastic tied through them as a head band, and you have a cheap, very tough head lamp as well.
Petzl's headlamps also make decent winkie lights or work lights, but it is best to have winkies facing front and back, so 2 cheap winkies are better than only one expensive head lamp!
http://www.mec.ca/Products/product_...older_id=2534374302697057&bmUID=1163958166213
Enlightenment!