Personal uses of Pi/Arduino: - Garage opener/security (door sensing / camera & push notificaitons to cellphone) (Pi) - 2-axis solar tracker with manual contro

Personal uses of Pi/Arduino: - Garage opener/security (door sensing / camera & push notificaitons to cellphone) (Pi) - 2-axis solar tracker with manual control & wind speed sensing (Arduino) - Home VPN Server (Pi) - Sump water level monitor (Pi) - Industrial temperature cable sensing and reporting device for reading from ~140 cables (http://www.advancedgrainmanagement.com/products/temperature-cables/ http://www.advancedgrainmanagement.com/products/temperature-...) (Pi) So as others have said, if you have the ability to do it you're limited by what you can imagine. If you treat the output in the same way you would any industrial automation you're virtually only limited by what you can imagine you want to do with the device. I've set up a Pi as a home media server (though that's extremely common). I've got a friend using Pi for underground sprinkler control.