I just finished my project which uses LPD6803 LED Modules to create a huge (80cm x 80cm) panel. I published a video on vimeo:
I send uncompressed raw image frames from my application to my arduino or teensy board, the uP will then update the content. With one message I can update 32 pixels (= half of the panel).
The source files are published on GitHub: https://github.com/neophob/PixelController
If you're interested getting such a panel, check out: http://www.indiegogo.com/pixelinvadersDIY?a=167555&i=addr