I would invest in a bunch of SD (TF) cards in 64Gb capacity each instead. They are dirt cheap today ($6 shipped). And make a library of your files stored by category. That's more versatile, lightweight, and much more reliable than mechanical hard drive. 1TB is usually more than enough for everything one could accomulate in a lifetime (except HD movies library of course ) 1000/64*6 = $93 - less than twice the cost of 1TB HDD and weighting nothing (0.3 oz). They also might have a trade value far exceeding $6.

I saw a lot of positive reviews for PowerFilm when been researching the subject some years ago: http://www.amazon.com/PowerFilm-Rollable-Solar-Panel-Charger/dp/B001UHAAAC - still on the market - means they are good. Just look around for deals. On other hand, foldable options are also good. The Nomad I have is extremely tough and has a very well thought out design:

That's probably refers to my opinion on the solar wattage I think is ideal. The folding pack is actually not that big at all: See here (also film based, by the way). The goal is to have enough power even in the evening or in a heavy overcast. I have been considering that one to power my field laptop at the time they were quite power hungry and smartphones too weak for my field tasks...

I have not seen them at this price. Can you list a source? I do exactly what you described and it works well for me.

If it's that cheap, it's probably a low class (slow speed) SD card. You can really notice the writting speed difference between the more expensive higher class cards. So unless you have lots of time left, having a higher class card will make thing easier and there for you will generally update your backup more often.

As for data, I would recommend to seperate files in to:
- Important documents (encrypt it)
- Memories (pictures and such)
- Others, not so important/replaceble (movies, music, etc.)

This allows you to decide which data to copy to which storage solution, if you have multiple storage devices. Having multiple storage devices at differnt locations is pretty handy if a location is effected by something (fire, flooding, etc).

I use a mixture of 2,5 HDD's, USB flashdrives and stored hidden in devices.

I do a backup of the user directory (Drive letter:\\users\username) except for the download folder. Any downloaded installation programs get copied onto a DVD-R. It's enough to reconstruct things in case of a drive crash. The user directory includes desktop, pictures, movies, music, my docs, contacts, favorites, etc.

Important or sensative documents are already encryted as a countermeasure in case I get hacked. Think of it as a cyber home safe. Like most people here, I prefer to make the odds in my favor.

Check the eBay. To be exact, last time I bought one for $12, but when checked yesterday - there were $6-7 offers. Just ordered one for $5.95 to verify if that's not a fake. The $12 one is class 10. However, most of the data on those emergency cards will be static (documents, photos, home videos, books, music, games). So I would not be concerned much even if that's in fact Class 4. Actually the older slow cards should be a bit more reliable (larger components). Even better to use old 2Gb cards, as they are made by SLC technology (not MLC as modern inexpensive high capacity cards), which data retention time is 10 years (vs 3-4 for MLC).

By the way, keep in mind, that any solid state flash cards/drives (SSD) cannot be stored forever as DVD disks (the later also depend on storage environment a lot, though). It is crucial to have them powered at least twice a year, and rewrite with the data every 2 years, otherwise the stored data may start deteriorating. Also, it is better to use fresh (brand new) cards for long term storage, as with every rewrite cycle the data retention time will be reduced. In that regard ordinary hard drives might look more attractive as they seem to keep data much longer, however, for hard drives, there are three main factors affecting their data retention time: magnetic field breakdown, bad environmental conditions, and mechanical failures. So, it is recommended to rewrite long term storage hard drives (which are sitting on the shelf, not powered) every 2 years as well, including a mandatory low level reformatting procedure.

I've been doing some poking around concerning memory stability vs environmental stresses. Flash memory cards are near indestructible, but the data will start to degrade sooner. They're really ideally suited for transporting, not long term storage, of data. I feel that duplicate flash memory cards are the best solution for scenarios where rough handling is expected, but data only has to be stable for a few months. If you've got the money, an IronKey D250 ($100-$600 ea) is a heck of a way to transport data.

HDD and DVD+/-R seem to be the big ones when it comes to not loosing data. HDD can tolerate slightly higher long term storage temperatures then DVD's, but obviously don't tolerate getting dropped as well as the ligher discs. JVC rates their archival DVDs at -20C to 50C for long term storage and -40C to 60C for <2 weeks, and WD rates their Elements external drive at -20C to 50C. Sandisk rates their SSD internal drives at 0C to 70C.

Alex, thanks for the tutorial. I have been carrying sd chips for years and seem to have had good results, but mostly by random luck.

Redundancy appears to be the best solution. I am an international traveler so in addition to sd cards & a portable USB hd, I keep a copy on the net. Well encrypted of course.

Nomad.

Yeah, it really works, as I learned yesterday when the HDD on my 8 year old laptop died (I do most of my work on a desktop), and the net loss of data was zero. I did have a short period of panic when I realized I had misplaced one of the backup DVD's, but found it after a bit of looking. Note to self: remember where you put the backups!