Hi!
The Centipede Shield would be perfect for my project!
I am trying to build a clock with two bi-color 8x8 led matrices.
It doesn't seem very original, until I tell you that the matrix is covered with a black film with the shape of a letter on each led.
The letters compose words and tell you the time in text.
The idea came with the World Clock Arduino version on Instructables (sorry, not allowed to post a link yet), only my solution is more compact (letters are reused between words) and hopefully more colorful 
I created two different films, one in English and the other in French (I am a true Canadian, what can I say ;D)
Alas I need at least 40 I/O's and that's without the RTC chip or the buttons...