I'm using a Sharkoon Sata Quickport Pro (same as the Freecom you are writing about, same as the Thermaltake BlacX Docking Station Joel is writing about) and two separate sata harddiscs the same size as my data drive.
One hdd is always in the quickport, so I can make a fast backup whenever I feel like it: just switch on the quickport, run a robocopy or synctoys script to refresh the backup. Very fast, very nice!
The 2nd hdd I keep in my office for offline storage.
Roundabout once a week I take the hdd from the quickport, take it with me into the office, swap it with the 2nd hdd, so now the 1st hdd is in the office, the 2nd comes back home into the quickport.
This way I always have a very recent backup at home, and in case of theft, fire or water damage I have an offline storage which is at most one week old.
Of course you'll need cases for your hdds, like the plastic ones Samsung delivers with their drives.