i dont know much about hard drives but i need one so i have a few questions. 1. Are there any advantages or disadvantages between the different interfaces?(usb, firewire, esata) Is there any difference in speed or reliability or anything like that? 2. I need one that is compatible with both pc and mac (notably the new time machine application). Are most hard drives pretty much plug and play and will work on any machine, or do i need to specifically find a mac compatible one? 3. Are there any other meaningful statistics i should be looking at? I know about capacity and spindle speed but is there anything else? 4. Whats the best place to buy one? I have been looking at tiger direct and newegg but is there anywhere else you would recommend? Thanks!