I just found a Nova Bull on ebay for $30 new (closeout of a retail store) but these look better. The Bull is a little large. It was the one to have a few years ago but I think the Bull is showing its age now.

I bought it after having three different incidents where people did dangerous things clearly because they didn't see me, even though I had a 50 lumen flasher running up front. I'm putting the Bull up there because it's a compromise. If I still get people pulling out to pass while heading for me, pulling out of intersections, etc with the Bull, I'll switch to a pair of 500 lumen lights set in "holy dammit what the hell is that" strobe mode. I can keep dialing it up until they see me.