I recently completed a public art project using the LPD8806 RGB LED strips (supplied by Adafruit Industries). It is quite large, a little over 25 meters (totalling 1328 LEDs). It works well, except I would like to bump the refresh rate as high as I can manage with Arduino.
Currently I use the SPI pins on a Mega 2560 which shifts through the entire strip impressively fast.
But, I want it to be even faster (of course)! Is the speed of the SPI interface tied to the central clock speed? Would I gain a speed advantage using a Due, at 80MHz rather than Mega's 12MHz?