http://www.chasecam.com/
I've heard some pretty good things about these, BUT they are serious money....
Here's another one:
http://www.cam-fx.com/
I've been researching 4-channel DVR's. I would really like one that does 4 channels:
1. Front
2. Rear
3. Left
4. Right
So you get a 360-degree recording. Preferably with GPS and a solid-state drive instead of a spinning hard drive. The cameras are pretty cheap ($19 on DX.com for non-HD), so it'd just be a matter of running the wires and investing in a DVR. I've seen two different models on the "budget" side of things. The first one is a windshield-mounted one with additional inputs, goes for under $600 on eBay:
http://www.ebay.com/itm/New-BEST-VI...ck-Box-Camera-Dvr-Drive-8GB-GPS-/110830654906
The second one is an actual black box (it's more aimed to the taxi/truck/bus market). The standard-definition models that run off SD cards start around $250:
http://www.ebay.com/itm/SD-Car-DVR-...-Audio-4-Pin-2-Reversing-Camera-/400500855353
There's a bunch on Ali Express too:
http://www.aliexpress.com/wholesale/wholesale-4%252dchannel-car-dvr.html
My buddy's Q7 got totalled when a guy cut him off & slammed on his brakes trying to make an quick left-turn from the right lane...and my buddy got the ticket & was "at fault" because of the law (he rear-ended the guy), even though the other guy wasn't even in his lane to begin with! For a few hundred bucks, it seems worth it to me to get an all-around-view DVR just in case. My buddy had just gotten a great deal on the used SUV and it was a real step up for him car-wise...boom, gone, his fault even though it wasn't his fault.
Similar story - my buddy ran a yellow light (did not turn red when he went under). A lady decide to jump the gun and drive through the red light on the perpendicular side of the intersection, got T-boned. She ran a red light from a stop; he ran a yellow light from a green while rolling. He got the ticket. No DVR, no proof, even though the lady said she ran the red, he still got the ticket for the crash.
I've also been hit several times. Once where a guy rear-ended me on the highway and I ended up chasing him down (which was stupid, but I was younger haha). If I had had a rearview DVR, I could have just shown the cops the video with his license plate and been done. I think I've gotten a little paranoid as I've gotten older
