[scardine]

Check out the talk "Militarizing Your Backyard with Python: Computer Vision and the Squirrel Hordes"[1] from PyCon 2012. He wired a water canon to a camera able to tell squirrels from birds:

> Has your garden been ravaged by the marauding squirrel hordes? Has your bird feeder been pillaged? Tired of shaking your fist at the neighbor children? Learn how to use Python to tap into computer vision libraries and build an automated sentry water cannon capable of soaking intruders.

Previous discussion here: https://news.ycombinator.com/item?id=3710107

[1] http://pyvideo.org/pycon-us-2012/militarizing-your-backyard-...