This was a quick proof of concept for me for a larger project. What I have done here is extend the tutorial here, which explains how to attach an Arduino to the file system of its host computer. I then managed the file by a php script, which is then exposed via Apache. What all this means, is that I can control the actions of my Arduino by clicks on my cell phone. A quick note, this can be modified to either access the Arduino by a local network, or with public DNS allowing you to control it anywhere in the world as long as you have a internet connection.