I know my Quicksilver G4 (2001) does not support internal drives bigger than 128GB. But what about USB or FireWire drives? Are they also limited to 128GB? Are USB drives truly plug and play regardless of what you plug it into? Reason I'm asking is that I will get a Wii later this year and I'm hoping that eventually the Wii will support external USB-drives for storage and it would be nice if a drive bought today will work for my mac, pc and Wii all at once.