Using Amazon S3 for backups under Linux

Dear Lazyweb,

Amazon's S3 services look very interesting for doing backups, but I can't find a perfect solution to integreate it into our current setup (using either rdiffbackup or rsnapshot).

Did anyone of you ever used it in a similar way, and if so, how?
My basic idea was:
1. mount S3 (via FUSE?)
2. mount some encrypted FS on top of it (EncFS?)
3. run rdiffbackup/rsnapshot as usual on the resulting encrypted bucket

Any suggestions on tools how to do this? Are s3fs and EncFS what I'm looking for?