QUOTE(chud @ Nov 7 2007, 02:27 PM) [snapback]412797[/snapback]
For me, this somewhat defeats the purpose of keeping the journal on paper (though not completely), but it *is* definitely the most secure way to keep it, and the only way with a reasonable chance of staying secure should a persistent and well-funded inquirer come round.
On Windows, you have to install some things -- I recommend
GPG4Win. That should include all the pieces you need to encrypt individual files. (GPG is the freeware Gnu-software version of PGP.)
On linux, it may already be installed for you, so just:
% gpg --encrypt --symmetric -o filename-you-want-for-encrypted-version filename-of-plain-version
It will prompt you for a passphrase to be used in encrypting (and later decrypting!) the file. Do not forget it! If you lose the passphrase there is NO WAY to recover it.
After it's encrypted you should securely delete the original. "shred" on linux will overwrite it, and there are various utilities for Windows ("Eraser" is a decent one) for securely deleting files. These should be good enough against anyone short of well-funded three-letter-agencies. (Against those, you probably need to really, thoroughly destroy the media with the plaintext copy on it. Thermite works well, I hear.

)
For my level of everyday use, GPG and "shred" or "Eraser" are quite secure enough, and easy to use. If anyone wants more detail help getting them going, feel free to drop me a note, I'll be happy to try to help.
You've covered it very nicely. Doug asked me to write up some pointers but I don't think I'm much help on that. I use regular PGP and have for many years and I'm not up on the latest tools out there.
In my original comment I suggested zipping and then encrypting but further thought on it makes me change my mind. Instead, I suggest encrypting and then emailing the files to a Gmail account you've set up for the purpose. Gmail gives you 3-plus GB of storage space, enough to store about 9,000 scanned 8x11 pages. Gmail can worry about backups and keeping it safe. The files are dated, easily retrieved, and available to you anywhere in the world. In modern parlance, they are "in the cloud".
Your encryption software wants to be something that's standardized and widely available so if your machine blows up you can easily download a fresh copy of the crypto software, fetch pages from Gmail, and as long as you remember your passphrase you're in business. You can recover and read your journal from any machine with access to the Internet. It would also be wise to choose crypto software that runs on Linux, Mac, and Windows. Then you are universal.
As far as scanning defeating much of the purpose of writing, it all depends on the individual. Some people think and compose better with paper and pen but are not so concerned about the paper itself after it's done. Sometimes, it's nice to have real paper. My daughter lives 2,400 miles away and she and I exchange handwritten letters and I enjoy getting the original paper written in her hand as she enjoys getting mine. But for some, the paper is not that important once the words are on it. In that case, scanning is a great solution. It can be encrypted. And you can make as many backups of the encrypted files as you want and put them in safe places, or email them to Gmail, or whatever.