Download a dashcam app and turn it into a dashcam. Buy a phone mount and cigarette charger adapter. You wont regrett it. If you get in one accident it will pay for itself. Also great for catching insurance fraud scams. You might even end up with a viral video.
You won't get much for it selling but you can use it to stream music or something. I also saw one being used as a controller for a DIY dumbwaiter recently.