This is a cool build where the author is using an RPi to controll a nerf gun Its all build with servos and a webcam and written in python. Reminds me of the opensentry project which uses an arduino and a windows laptop. I like this one better cause the cost is lower and linux based (well python can run windows too).
http://hackaday.com/2015/10/03/raspberry-pi-sentry-turret-is-the-enemy-of-all-mankind/
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