Yes..
In Snow Leopard use the Disk Utility for create a password protected disk image of your project folder
1. Open up the Disk Utility application, found in Applications > Utilities.
2. Go to File > New > Disk Image from Folder... (or use the keyboard shortcut, Shift +
Command + N).
3. Locate the folder you want to add password protection for and click Image.
4. Change the file name if needed.
5. For Image Format, make sure to select read/write so you still have access to edit the files
in the folder.
6. Choose either 128-bit or 256-bit AES Encryption. Click Save.
7. Now it will start creating your disk image, and it's time to enter your password. Enter your
chosen password for the folder, then verify it.
8. Un-check the box next to Remember password in my keychain—if you don't, adding this password is pretty much worthless. You could always remove the password from your keychain later, but it's just more work. Just un-check the box.
9. Press OK and wait for it to complete.
Done. Now whenever you go to open the .dmg, it will ask you for the password. It will then un-encrypt the data and mount the .dmg.
Finally, Always remember to eject the dmg after you have finished otherwise it will still be left open and accessible by the Engineer after you have left