I wanted more tail lights on the back but didn't want to wire them up.
So I headed over to a bicycle shop and bought the brightest tail lights they had. I strap them to the turn signal stalks and they work great. They give me much more visibility from the rear. They run on 2AA batteries. And last about two months of night riding. The lights have four modes; flashing, constant, random flashing and inline flashing. I use constant. I don't know if it is legal to use flashing. They also have quick release, so I take them off when not using them. Can be used vertical or horizontal reguardless of how you mount the strap.
http://www.cateye.com