I was hoping to get some advice on external hard drive recommendations. I've read the mac rumors hard drive guide which is really helpful, but was hoping for some direct input. So here is the scoop... Currently, I have two WD passport portable external hard drives - one for storing music (100GB) and the other for time machine (250GB) which i use to backup my old but still working Power Mac G4 and music drive. I just purchased a new 15" MBP (320 GB) and am looking to expand my storage capability (either for adding more music capacity or time machining my MBP or both). I just purchased a new Seagate Free Agent Go today (320 GB for $90), but I'm rethinking that purchase. I really like the portability, proven track record, and price point of the WD passports and Seagate FreeAgent Go external drives. However, my primary concern is that they don't have an ac adapter which can cause problems when macs goes to sleep. Does anyone consider this an important feature to have? If so, I would appreciate hearing rationale/philosophy around this and any alternative recommendations. Plus, it would be nice but not required if there was a firewire option. I find that USB 2.0 is relatively slow, especially when doing lots of reads/writes in itunes. Any and all advice is really appreciated.