The Online Thermometer project in my book "Practical Arduino" is a nice demonstration of using Arduino to connect sensors to a network and make them accessible online, but it was based on a version of the Seeed Studio Ethernet shield that is no longer in production. Many people have asked me how they can modify that project to make it work with an Ethernet shield based on the popular Wiznet W5100 chipset, which includes the official Arduino Ethernet shield and also our very own Freetronics Ethernet Shield with PoE Support.
So I've created a modified version of the sketch using the very cool Webduino library, and the details are written up right here:
