There's a new raspberry pi1, called the compute module1. It's meant for integrating with other systems, rather than just using as a standalone computer. This is the sort of thing I should use for my own home automation, but (like with using an arduino instead of just raw components) the existing raspberry pi gives more flexibility for prototyping (you can plug a keyboard and monitor straight in for example).
arduino: Microcontroller, hardware prototyping platform, a tiny specialised computer.
raspberry pi: Credit card sized super cheap computer, awesome.
Paul Clarke's blog - I live in Hythe in the far South. Wed + father to two, I am a full stack web engineer, + I do js / Node, some ruby, python, php etc. I like pubs, running, eating, home-automation and other diy jiggery-pokery, history, family tree stuff, Television, squirrels, pirates, lego, + TIME TRAVEL.