I just found and starting using some great and really cheap LED matrix displays (8x32 in the ones I got) that are really easy to use and can be linked in chains of 4 displays.
Sure Electronics sells them on eBay and from their site: http://www.sureelectronics.net/goods.php?id=907
However, they are located in and everything is shipped from China. Not a huge deal, but the ship times are kinda long and I bet that we could get better prices if they were bought in bulk.
They also have many other display models, the linked one above is just what I got and probably their most popular.
On a side note, there is a really great arduino library for interfacing with them here: http://www.makehackvoid.com/member-proj … ontrollers
I’ve actually never even used an Arduino board before this project and I was able to get them hooked up and displaying a text marquee using that library in under 10 minutes.