http://www.adrive.com/
Another solution for you that might be cheaper then R1Soft would be simply to purchase a shared hosting plan and simply forwarding the backups to that account's FTP but R1Soft would definitely be best solution if you can afford the price. How big do you expect your backups to be?
-John
My VPS has a 100 GB disk space
I use 10 GB of disk space.
This can further increase