or anyone else that wants LEDs that are bright enough to light a whole amp rack.

Check out the Lumileds LED's. The 1W versions needs about 500ma when using PWM or 350ma staright DC. There are larger models too. I don't know if that board will be able to control them but, if it can switch one and off 5V or 12V then it will work easily with the current regulators I built for them.

I am sure some of you have to have seen these right? Turbocad used them to backlight his LCD. I have a bunch laying around that I used to sell as a package pair. They used to be expensive but have come down in price over the years.