Machine learning for identification of cars by Dzidorius Martinaitis.
A very awesome post (with code) on capturing video from traffic cameras and training your computer to recognize cars.
The post covers using video from public sources but the thought does occur to me that you could spool the output from a digital camera attached to a telephoto lens to a personal computer for encryption and transfer over the Net. So that you could get higher quality images than off a public feed.
I am sure you will enjoy experimenting with it both as illustrated in the post and as other possibilities suggest themselves to you.