From Apple's Time Capsule page: Stay plugged in. Time Capsule is a great wireless backup solution for notebook users. For your backup to initiate automatically, your notebooks power adaptor must be plugged in. Conserve your battery and guarantee that your backup session completes in its entirety. Does this make sense to anyone? Surely the whole point of TC, is that notebook users can backup wirelessly. If you have to plug in your power adaptor for auto backups (the whole point of TM), you may-as-well just plug in a normal hard-drive anyway, it would probably be a cheaper option. Is there anyway around this? I'm thinking of getting a TC to use with my MB, but this is putting me off. Thanks for any help.