Multiple copies....

Source data on my main computer, managed with Lightroom in year folders, data gets migrated every few years when I buy a new bigger hard drive. Second copy of all my source files on a RAID box connected via ESATA. Third copy on an external hard drive stored at mums away from my house.

I then have my developed photos, I keep a key set on my computer, a copy goes on my RAID box, another copy on the hard drive at mums, another on my personal USB drive I carry with me to work, plus each photo uploaded to Flickr.

My source data is good up to a nuke going off over Sheffield, my developed photos are good whilst ever we have electricity !