I've completed my second arduino project - displaying the latest tweet from my friends' feed.
It uses a 16x2 LCD screen and an ethernet shield (and an arduino, obviously). I use a PHP twitter API and a PHP web page to show a single tweet in a suitable format.
The arduino grabs that feed and shows it on screen. The top line is twitter name and time of post, the second line scrolls the tweet.
The code is available on my site:
http://cowjam.net.

Comments or suggestions on improvements welcome.
CowJam