Just a thought about using NASD as your on site backup. You will have to make sure that you know how to set your NASD to act as the backup. I bought one to use at home, and its great as a server, but becasue of the way I have it set up I am unable to set it as my computers backup location (I can probably figure out how to fix it, but it was not a big deal for me).
In terms of off site backups, you can probably use the same type of divice (NASD) through a VPN from home. It all depends on what your institutions firewall settings are.
Hope that makes sense.