Driving home last night I saw what I thought was a cyclist in the bike lane. He had a white (!) blinky as a tail light, so it was hard to judge distance (or even determine if he was on a bike). He did, however, have reflective material on his cranks and ankles. My truck's lights really picked up the movement of those items, and made it a whole lot easier to identify him as a cyclist (except that his single pannier obscured his left ankle band/strap).
I was amazed at how much more effective the reflective material was when it was affixed to something that's moving. This doesn't obviate the need for a properly-colored tail light, but just a few strips of strategically placed reflective tape can really improve your visibility to motorists.