I've been wanting to do this for a while having gone the cigarette lighter route prior...
I was thinking of working in a separate circuit from the battery with a power relay run through the ignition, mounting it all in a small Pelican with USB A female plugs soldered to a PCB... However, I can't think of a creative way to weather proof the wires that would passing across the seam of the Pelican...
http://www.pelicancases.com/1010-p/1010.htm
Ideas?
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