Yeah you could do that with the USB hub or go for a more creative solution as I did. I found that the external power does not power the processor in the USB hub, this requires power from the USB coming from the computer. Therefore you can cut the trace and separate the power so that the external power supply only powers your ports and the computer continues to power the processor inside the USB hub.
http://inov8tr.blogs.com/scooby/2006...b_solutio.html
As for the Firewave, I have decided to risk a little extra power drain than try to hack the firewire cable or the firewave. It seems that the power drain would be minimal as the Firewave isn't doing anything when the computer is sleeping. I just installed everything today, so time will tell if there is going to be an issue.
-David
CarMac Install 98% Complete
http://inov8tr.blogs.com/scooby/