No promises, but I think we will enable this on rsync.net storage arrays...
We already have s3cmd in our environment, so you can:
ssh user@rsync.net s3cmd get s3://rsynctest/mscdex.exe
So if we put this into the environment, you could call it over SSH:
ssh user@rsync.net gmvault sync foo.bar@gmail.com
... which is fantastic.
More like this.