I really don't think it's in your best interest to offload the data to a passive storage media. As quickly as storage is increasing, it's not unreasonable to literally keep every picture/movie you've ever taken, every email you've either sent/received, or any other piece of data you would vomit over if you lost it with you via either a network share or a local resource.
Personally, I keep a RAID-1 mirror established with some non-system internal SATA drives and have an external USB drive that I periodically back up to. When we leave for a vacation, I just lock the drive up at my office.
I wish I could say I was disciplined enough to have two external drives and keep swapping them between my office and home, but I'm not there yet.
Bare-minimum, if I get hit with a nasty piece of malicious code or do something just plain stupid, I've only lost the delta between then and the last backup. If it's a simple drive failure (which has happened more than once,) I'm covered.