I have just inventoried my processed images - my keepers if you will - 380 gig of images that I cannot afford to lose (after all they produced two books).
At 15 cents per gig per month, my monthly charge (assuming no access) would be $2 for Jungle Disk, $57 for the storage and extra fees if I upload or access any of my stored files. This amounts to something in the order of under $1000 per year including those upload fees. I can think of a lot of things I can do with $1000 and probably so can you. Certainly one more 1 TB external drive will be around $200, but doesn't automatically back up and disconnect from power and any other connections that could be damaged by a lightning bolt or major power surge.
I do take my image files to the office for off site storage, but do it far less often than I really should. Perhaps I should just cough up.
Now, the vast majority of those images don't get edited month to month - probably fewer than 5% get edited in a year - after all they have taken 6 years of digital work to collect. Put that way, the sensible thing to do would be to back up everything I now have to a hard disk, unplug it and take it off site (as well as keeping local backups with my Drobo). I could then use something like S3 to back up all the new edited images (and any changed images from before) and once a year, put them onto a new hard drive, delete everything at S3 and start over with new edited images yet again.
In 10 years I will have accumulated 10 partially filled off site hard drives but only paying Amazon to store one years worth of images. This way I get automated off site storage (almost no effort on my part) for a modest sum of money (and once a year I have to back up my images to a hard drive. Given that I can back up all my processed iamges to one drive, it probably even makes sense to back up everything to each yearly drive so there is redundancy even in the off side hard drives.
What are you thinking about reliable painless off site backup?