I've wanted a dash cam for years but the technology just wasn't there. In the late 90s I drove around with my JVC GR-DVM70U miniDV camcorder on a tripod lashed into my back seat. No I can have 1080p video from my cellphone mounted on a windshield mount. I have lots of video but it's pretty limited due to storage limitations I choose the highest quality because my reasoning is if something goes wrong there's no point…
A better option might using a service like UStream. Download their app, set your channel to private, and when you drive places, start your broadcast. I believe they automatically archive anything you livestream, so if something happens and the phone is destroyed, there's still a record of what happened. And it wouldn't fill up local storage. With an Android phone, this might even be scriptable using something like Ta…
I thought about UStream but I am lucky to get a signal even here in the capital city; GPS or cell.
Maybe a RaspberryPi, a small webcam and solar panel.