Anyone who has shared a computer with a roommate, family member, or co-worker knows it's pretty hard to keep everything organized. But beyond having separate user accounts or personal folders, some data you have on your hard drive just isn't meant to be seen by other users. Whether it's your personal account numbers, journal entries, or other private files, a secure place to store items on your shared computer is necessary for your privacy.
A while ago I found a great Windows app for creating secure volumes called TrueCrypt. This open-source (free) program offers up multiple levels of security and several different types of encryption. It's so secure that if you forget the password to your encrypted volume, you might as well just trash it. Not even your favorite computer-fixing buddy down the hall in your dorm can crack this code...seriously. Just to give you an idea, TrueCrypt uses encryption algorithms AES-256, Blowfish (448-bit key), CAST5, Serpent, Triple DES, and Twofish, or just about any combination of these methods. Don't worry, I don't know what all that means either, but TrueCrypt offers a wizard taking you through a step-by-step process explaining how to create secure volumes, how to select your encryption type, and how to create a secure password.
The big news today is that Truecrypt is now available for Mac OS X. The only catch is you'll have to download the version that is specific to your OS (Tiger or Leopard) and processor (PowerPC or Intel). I've rounded up all four Mac versions of TrueCrypt here.
Once you set up your secure folder, you can now rest assured your nosy roommate has no chance of reading your journal entries. Just remember, if you forget your password, you won't be able to read them either!