How does everybody backup? 19 years ago
Jungledisk is great. Its easy to use, cheap and runs on Windows, Linux (includes GUI and CLI) and Mac. You can treat is as a network drive or setup automated backups. The protocol is open so you can use tools like S3 Firefox Organizer to retrieve your data outside of the Jungledisk front-end.
Another big plus is that you can run an unlimited number of instances across any number of machines after paying a one time fee of $25.