iPod Video (5.5g) can be upgraded to 240GB easy.
Know where I would get HDs and research compatibility for it? Upgrading the hd never really came to mind, as the ipod isn't exactly meant to be user serviceable, and that I would probably have to use some apple only tool to format the new hd.
Also, I would switch to something non-apple if I could, but those android players seem like overkill and I am a bit used to the simplicity of the ipods controls.