I wanted greater visibility from the sides of the bike.
I took off the side reflectors at the rear and replaced them with red LED lights from superbrightleds.com.
See
http://www.superbrightleds.com/moreinfo ... module/18/
Price is $6.95 each and they can easily be wired to a tail light.
These are really bright in the daytime and certainly eye catching at night. Having been hit from the side by a car a year and a half ago, I felt that some better side warning was needed. I'm now thinking of amber lights for the front reflectors.