- Download Truecrypt, create a 1MB Truecrypt volume, use a four word password: http://preshing.com/20110811/xkcd-password-generator
- Stop your Bitcoin client and locate the wallet.dat file, copy it into the Truecrypt volume
- Save a copy of the Truecrypt volume on Dropbox, Google Drive, Skydrive, Gmail and on your local disk
- Test using the wallet.dat file from your Truecrypt volume in a new Bitcoin client install. Works? Delete the original wallet.dat and all unencrypted versions.
This is, IMHO, the easiest and best way to secure a wallet with "savings" that you are not going to use regularly.
Regards,
Tagide