This might not be exactly what you have in mind but it is an easy way to back up tons of data, fast, and cheap.
We have a SME 6 file server with about 40Gb of data on it. Using a program called Syncback, running on a Windows machine, I can back up over the network to a USB drive attached to the Windows machine or from home over the internet through VPN (incremental back up only).
Synback is a free download and is pretty powerful from my limited experience. It allows the entry of passwords to access the data over network, password protection of data, compression (obviously), FTP site as destination, email notifications, etc.
Now if only I could get the iSeries to do this...
Hope this helps