Tuitwall is a project that will allow you to show Tweets in a LED matrix. It’s based on an Arduino, an Ethernet shield, a LED matrix that has its controller, a Holtek HT1632C and a PHP backend that interfaces with Twitter. Its designer Santiago Reig explains: “The webpage, written in PHP, allows a user to login with their Twitter account and show their Tweets in the LED matrix. It also shows the status, as the last Tweet shown, logged user, type of Tweets (timeline, mentions, your own ones) and optionally a video stream. There is a configuration file, so lots of things can be tweaked to your liking or needs.
The Arduino calls a PHP page at the backend that returns a string ended with chr(0) that is what is shown in the LED matrix. If DHCP is activated on your network, no IP configuration should be needed by the ethernet shield. It sends debug information through the serial port, so you can see the status and any errors that occur.
This Arduino part is detached from the project, it has no dependency on the rest of the project to function properly, so you can change the PHP page it asks for the data and show in the LED matrix completely different information, like weather report, current playing song, RSS feed, etc.”
You can get more detail about this project and all source code form GitHub.