I was talking to a friend yesterday and he is using Aamazon's S3 and other stuff for (among other things) web development. What is S3? Basically a file storage with a web interface. You can put file there, but not whole directory tree (i.e. not a full blown Unix filesystem). You must create a bucket which gets a unique ID and then you can create objects in there which are up to 5 GB in size.

Turns out there are already backup programs out there which us S3. I was thinking if rdup could be modified to also use this service.

And then I hit me

Nothing needs to be changed in rdup. The output of rdup -c is exactly what you want to put on S3 (encrypted of course). I have no code yet, but it will work along the following lines: ($ is the prompt)

$ rdup -c <whatever-x> | rdup-crypt > mega-encrypted-rdup-file
$ w3c -put -dest <whatever-y> mega-encrypted-rdup-file

Restore works the other way around.