This:
http://www.amazon.com/Black-Box-A118-Stealth-Dashboard/dp/B00NG84AT0It is $68. It was super easy to mount and I had it done along with hiding cables in maybe 15 minutes. It is mounted up in front of the rear view mirror with the cable routed all the way around the windshield, down the driver's side pillar, over the steering wheel, and down into the console for the 12V Adapter. It helpfully included a bunch of little 3m stick on cable management deals for the the couple of spots I needed to cross that didn't have anywhere to stuff the cable.
Power is supplied by mini USB so if you had USB ports you could get the appropriate cable and power it that way. A good case would be you have multiple usb devices to charge (like a cell phone) so you get one of these dual usb 12V adapters. It includes a cigarette lighter adapter.
It requires up to a 32GB micro SD card.
Did a test run around the neighborhood and the video is pretty good for a $68 camera, more than usable for the intended purpose. I'll take another drive tonight to see how it does in the dark.
Issues so far (all pretty minor):
1. I saw this on other reviews, at some sun angles in when cloudy the video is very dark. Something about it fakes out the light sensor. You can see that very clearly in the first video. It's fine, but not ideal.
2. The SD card is kind of difficult to get in and out. It is the standard spring loaded slot, but it is inset so far you have to poke at it with a key to get it to eject, then it ejects with a lot of force so you need to be ready to catch it.
3. The mic is super sensitive. I was a little congested so you get to hear my nose breathing very clearly.
Videos (they are still uploading, give it a few minutes if they don't work):
https://youtu.be/5mhbSgl2ceUhttps://youtu.be/Mo7MxQeSouYAlso note: youtube blows goats, the video quality is notably better than what youtube has it at. The artifacts in what you see are not in the video files.
The first test had me really questioning the video quality, then I realized there was protective plastic sticker over the lens.
All in all - think for $68 it is a good buy.