We all know that security is a big issue these days, especially on the studio level, so here's a tip to add an extra level of security to anything you send out...
Make a sparse disk image using the disk utility application. Here's how:
1. Open Disk Utility.
2. Make sure you have nothing selected in the list of drives on the left side of the main window.
3. Select New Image.
4. Choose your settings. Be sure to set the volume size at least as big (or bigger) than the file(s) that you are putting inside your image. Select encryption. Select sparse disk image.
5. Press Create.
6. When prompted, enter a password. Uncheck Remember password in my keychain. (this will enable you to verify that you have created a password protected file)
7. Click on your newly created disk image to mount the "drive" if it's not mounted already and drag your file(s) into it.
8. Dismount the drive.
9. To double check that your file(s) are password protected click on the disk image and you are done.
10. Remember to tell the person receiving your file(s) the password

We use this method a lot on the movie that I am on right now. We still have to do all the burn-ins, etc. but an extra layer of security makes everyone feel a little more comfortable.