Good evening all: I have a question about storing photos from Aperture onto an external hard drive(s). I currently have an early 2008 iMac and I have a WD 1TB external hard drive connected to the Time Machine. I would like to Daisy Chain a larger external hard drive to the back of the computer and put the original WD external at the end of the daisy chain, just to have a fail safe in case the desktop goes down. Any ideas on which model to get? What's better to use - Firewire or USB? Do any models have Thunderbolt, FW and USB's on them? I'm looking to spend about 300 on the drive. And I would eventually like to upgrade the desktop to a new iMac in the future so a Thunderbolt system would work as well. Any help would be appreciated! J. R.