My iMac (just over a year old) has a reasonably large HDD of 1TB but my iTunes collections is starting to get rather large (500GB and growing) since I have starting ripping our DVDs and Blu-rays. Trying to determine what size external drive and type to get and how to set it up. FYI.....the iMac will be hardwired to the network as well as all ATVs throughout the home. Here are a few idea I have been brainstorming: 1. External drive for iTunes library + a second external drive for backups of both the iMac HDD and the iTunes external drive. 2. Same as above except using a RAID1 setup for the iTunes. **I don't have any reason why I would choose this over the previous setup but have read several threads about that sort of setup. I understand what RAID is and isn't but just not sure why I'd do that over a standard external drive.** 3. Something else? Totally open to suggestions. Thanks for any advice or suggestions!