jimbarstow:
I'm think of doing a project handling large data sets which would tax a single arduino. For that, I'll build a distributed network of arduino's that communicate with XBees.
That doesn't seem like a very practical way to handle large data sets - it would be a very expensive and complicated approach and I wouldn't expect it to be at all cost effective. Microcontrollers are simply not designed to be efficient data processing platforms. If you want to handle large data sets, you would be better off doing that on a different platform.