I love the Arduino as a simple and accessible controller platform for many varied projects. A few months ago, a purchased an Ethernet shield for my Arduino controller to work on some projects with a mate of mine - it was a massive hit - for the first time, I could control my projects remotely using simple software.
That got me thinking - The Arduino costs about $30AUD, and the Ethernet board cost about $30AUD as well. That is a lot of money - Could I make a simple, dedicated remote controller for much cheaper? Why Yes I could. Could I make it the size of a credit card? Why Yes - I could!!
This project is my simple Arduino compatible controller that has embedded Ethernet, and the capacity to drive some extra I/O lines for projects, such as a Remote thermometer, a Remotely accessible Fridge controller, and a Remote Humidity sensor. I have to say from the start that I didn't write all of the software, my mate Mikal did that - but this instructable is about making your own controller board