I have used up the USB's for time machine on the two current model Extreme's I have. I want to buy a Time Capsule to be used solely as a time machine, not for routing or wireless. Are there any alternative products? I read about using a Raspberry Pi but its quite expensive given you have to buy a powered external drive too, and a current model time capsule is only £5 more than a current extreme when they appear in the refurb store. When its in the refurb store the current model timecapsule is £149. Whats the best value? Does the old flat time capsule ever appear in the Apple refurb section anymore?