I wanted to make a marquee out of LEDs to show the high scores and the game being played at that time. I've now realized that would be too hard to map, but I can create graphics of each game to scroll by. The signs that I have are too large for a marquee, but I can make a custom sign out of the LED modules. The modules in one of my signs are 8X8, so you can pretty much make any size you want by linking them together.
The software I have allows you to select the number of rows/columns when it boots up. You also have to select the color for each pixel or you can import from a *.bmp file. Pretty cool, I just haven't had the time to sit down put it all together.