MOTM

> Is there any electrical reason why I couldn't simply swap the red LEDs
> on my 101 and 390 modules for blue ones, or possibly some other nice
> color like ultraviolet or sea green? Would I have to do anything
> besides just soldering one in place of the other?

Yes. They have a different forward voltage and current. You'd need to 
adjust the resistors to compensate. Depending on the circuit the extra 
current load might cause subtle problems too. Don't know for sure, but 
don't ask Paul, he doesn't like blue LEDs ^_^

Also, It's not an electrical reason, but looking at UV and bright blue 
LEDs is not that great for your eyeballs. You'll also probably drop the 
resale value of your modules, or maybe not. It's also impossible to 
find the MOTM style led in blue, aqua, or UV.

--mikes