You could also use this thing, a "Cloud NAS": www.cloudengines.com. Basically a device that exposes itself as a drive via SMB/CIFS and works exactly like a normal NAS, but it's hooked up to a cloud backend, so there is no local storage and it scales. Costs the same as Glacier (1c/GB/Month), but without the retrieval fees. Plus it won't take days to get your data! Obviously it won't run out of the box as a backup application since it's just a drive, but you could do pretty much anything with this thing that you could do with a normal NAS as long as you don't need blazing fast performance.