Most of those methods are easily breakable, and do not offer much security. Apple has a built in method to create a secure disk image, which is more or less a virtual disk, but you can consider it a folder for all intents and purposes.

In your Utilities folder, open “Disk Utility” and click on the “New Image” button. This will pop open a panel that looks like this.

You should be able to see the changes that I have made. Choosing 128 bit over 256 bit should be more than sufficient for most home users needs. Both are secure, 256 bits come at the expense of some performance. 128 bit, with a strong password, will take years and years for someone to crack.

The only troubling part of this is that you have to chose the size of the disk image you are about to make. 10MB is as small as you are allowed. You will end up with a 10MB disk image that you can store anything you want inside. However, if you ever need to store more than 10MB, you will be out of luck.

This size problem is easy enough to solve, just create a new larger disk image, and copy your old files to it.

An alternative is to create the format as a read/write sparse image. This will allow you to make it a minimum of 10MB, but also allow the disk image to dynamically grow to whatever size you desire.

When you click “Create”, you will be asked to enter in a password. Enter it in twice, to make sure you have it correct. You are now left with a single file, in this case, called “secret-folder.dmg”.

Opening that will open a virtual disk, that you can treat as a folder. You will be asked for a password to do so. I suggest not saving it in your keychain.

When you are done, and want to lock up your files, just drag the disk image icon to the trash, but keep the .dmg file, that is where your secret files are.

You are free to move and store this dmg file anywhere you like. It is a single secure file that can contain files and folders, just like any other files and folder. You can safely ftp, email, and transfer it to other Mac’s, and it will be openable on those machines with the correct password.

I am planning on keeping a secure disk image one on a USB thumb drive, specifically the OCZ Rally 2 series. I feel confident, that as long as my password is not in a dictionary, and is not guessable by anyone, that my most guarded secrets would be safe.

You may want to read our Understanding file downloads and their remnants, in order to get an understanding of how dmg files work before you embark on this.

This is a question we get frequently, if I have some time, I will try to clean up this reply, and turn it into a more detailed post for others.

Hope that helps.

If you want a very simple method, you can use an Automator Action, which is more something built into OS X. I have used this one for ages, and it works well for me.

If you want a standalone app, there is Name Mangler which as far as I can tell is free still.

If you want a very simple method, you can use an Automator Action, which is more something built into OS X. I have used this one for ages, and it works well for me.

Once you wrap your head around SpotLight, and I would say to not even bother in 10.4, but in 10.5 Leopard, it is quite a useful search tool.

More to come, thanks for the comments.

http://www.hexmonkeysoftware.com/

Thanks for the comment.