Anybody built a set of side marker lights that flash in sync? I'm thinking of something like the amber hazard lights used on farm equipment: near-360 degree visibility, placed at the outside edge of the vehicle, (I'd want a bar that would mount to the back edge of my rack to hold the lights just outboard of the panniers.) and flashing about 1-2 times per second.
Unsynchronized lights tend to look like multiple objects, or worse, like a turn signal, (though the ability to put one on solid while blinking the other as a turn signal would be nice) so I'd want them both running off a single controller. I know there are LED versions of the double-sided lights commonly used on tractors, but I'd prefer something in a 6V (or lower voltage) design so I wouldn't have to find somewhere to put a SLA battery or a huge lump of AAs.