I would like to put a video camera (webcam, whatever) mounted either under the rear view mirror or just sitting on the dashboard constantly recording. However, I don't want to keep the recorded video most of the time -- just in the event that something happens (i.e. car accident). I'd want the video to be automatically deleted after a short period of time (1 day perhaps) unless I tell it to not delete it. Does anyone know of any software that does this well?