Arduino Pager with Google App Engine

Today I decided to turn my arduino into a pager (albeit a not very portable one). The project had two parts.

1) A Google App Engine application that would store messages submitted via a HTML textbox and provide a way of querying these messages.

2) An arduino sketch that would make requests of the web app and display the results on an LCD screen. Here's the result:

http://mattywpager.appspot.com/

The hardest part was working out how an arduino can query this app using the shared ip address of appspot.com. This was acheived by using wireshark to see what my browser was doing. The resulting sketch simply sends this to the client

    client.println("GET /last HTTP/1.1");
    client.println("HOST: myappname.appspot.com");
    client.println("Connection: keep-alive");
    client.println("Cache-Control: max-age=0");
    client.println("Accept-Language:en-us,en;q=0.5");
    client.println("Accept-Encoding:gzip,deflate");
    client.println();

The whole thing took about 4 hours. But was great fun.