This shield could be used as a stand-alone transponder key, or with Google’s servers to create a cloud-computing application.

 
It’s time to present you an application with RFID. We want to show you how to use the popular Arduino to produce a device capable of recognizing passive transponder (TAG). But this is not the usual RFID key, because the system can …

A very interesting feature of Arduino is the great avalaibility of library that make the developer work very simple and fast.
Make a Web Server, a Web Client or post a Tweet haven’t difficulty.
Try to do the same application with the Microchip’s Stack TCP/IP…. It’s not impossible but for beginner developpers is of course hard.
With the Ethernet shield or WiFi shield …