I have a Macbook Air, with a rather small flash-based hard drive, and two Time Capsules -- one 500 GB and the other 1 TB. I am using the larger TC with Time Machine as a backup to the Air (and to another Macbook as well). And I have set up the smaller TC to act as a wireless hard drive to store material that won't fit on the Air. This seems to be working well enough, but so far as I can tell, the files on the smaller TC are not going to get backed up to the larger one. Is there a way to make that happen? Is there some way to tell the Time Machine on the Air to look at the external drive too when backing up? Thanks.