I've upgraded and now have this spare...
Turns on and off with the ignition (when connected to to a switched live power supply), and records 2 / 5 / 15 minute videos automatically. As soon as the card is full, it deletes the oldest video, and repeats forever.
Mount it in the windscreen, connect it up, and never touch it again - it'll just keep recording for you whenever you drive.
Records to an SDHC card (not supplied)
Camera is used, with some very very small scuffs on the lid.
Please note, it comes with a box but NOT it's original box. The box is for an HD camera, this is just SXGA. The box was for a warranty replacement camera, and includes a brand new power cable, mount, USB cable etc - all of which are unused and fit this camera fine.
Sample videos recorded with it:
http://youtu.be/QpCn5S9qWCg?hd=1
http://youtu.be/17L6jJcjde0?hd=1
£20 delivered