Here's a New Year's resolution that could save your identity, political career, or marriage. Recently, I was at an artist's house, fixing her Mac. Like many artists, her computer was a mess of files everywhere. I sat down to make a backup before the repairs, and I noticed she was hovering over me with a nervous look on her face.
"Don't worry," I assured her. "I'll find everything and make sure it's all backed up."
"I know you will," she replied, "But.... Don't look in the folder labeled, "Images from Peru".
This was a good point to stop the operation, and start a little Computing 101: Securing Files from Prying Eyes. The process is dead simple, and this website outlines the process on a Mac quite clearly. Basically, you use Disk Utility to create a Disk Image (you're already familiar with disk images - every time you download an application or update, you're downloading a disk image). Choose a size based on the amount of files you have to hide, and select AES Encryption from the drop down menu. Create a password, save the disk image, and you're ready to go. The new disk will appear in your sidebar - just like a flash drive or DVD. Copy the files over to your new disk, and hit the eject button. Now test to make sure you can open your archive before deleting the originals. Double click the Disk Image. It should ask for your password, and then mount again on your sidebar. I use this method to secure scanned copies of passports, credit cards, and a text file full of passwords. You can even use it to secure those images from Peru.