We want to buy my sister in law a mac that will work with the new iPod Nano we just got her, which needs USB 2.0. She has an old iMac (original ones, with crt! it;'s that old.) I'm assuming you can't update that mac to work with usb 2.0, so we want to get her a used imac or powerbook or macbook, or something that will let her use itunes with her nano etc. Anyone have a list of when/which models USB 2.0 was implemented in powerbooks, imacs, etc? thanks!