The other day I saw a cyclist riding by with a single red tail light blinking at fairly slow intervals. It was a bright sunny day, but the slow flashing red was amazingly bright, and seemed to me likely to significantly enhance the awareness of drivers about the presence of bicycle.
So I'm interested; do others ride with a daytime running light of this sort? And if so what do you recommend? (Unfortunately the guy was going a little to fast for me to ask at the time).