I was looking at the hotshot after many others and the rack-mount option, thought I'd cruise the forums first for an idea I had. Didn't find it, so maybe it's new? Due to the Hotshot having some poor reviews for it's mount (seen here:
Cygolite Hotshot Review - The Bike Light Database and elsewhere) I was thinking about zip-tieing an old seat post or similar tube (PVC, broom handle, whatever) to my rear rack and then being able to mount whatever I want to it. Granted, seat post-mounted lights would then be sideways, so possibly not ideal. I have a topeak MTX fold-up pannier bag that's 9"-10" wide and I was thinking a cross bar back there shouldn't be wider than say 12" to reduce the risk of catching it on anything. I think my rear rack is aluminum, so not sure I'd want to try welding anything on there. If it was steel, maybe. I was even thinking I could rig something with springs so that if anything does catch the end it would just swing out then spring back. I'd like to hear your thoughts and whether or not anyone's tried this? Or perhaps this should be moved to another thread?