I'm so glad you posted this suggestion. I installed my own cam and battery (not as elaborate a set-up splicing wires, soldering, and routing holes like
@nhirsch) and have it plugged into a cigarette socket splitter with a built-in switch that lives under the compartment arm rest. I did this to have a switch so I could turn it off overnight in my garage since my commute isn't long enough to charge the battery fully. Remembering to turn it on is easy, but remembering to turn it off is much harder without a visual clue.
I was planning to hardwiring a rocker switch but couldn't find a unobtrusive place for it in the center console. A wireless switch is a much easier solution and I could easily just Velcro the remote on the phone cradle mat, which would be an obvious reminder to turn off the cam when I get home for the night.
Do you have a suggestion on a good 12V wireless switch? There's a few on Amazon and eBay but reviews are scant.