Stick it in a jewel case, put in in a padded envelope and mark it FRAGILE. If you use one of those cardboard box foldable things from the post office, make sure you tape it up. Remember that postmen are thieves, it's in their very nature so if it's important get at least recorded delivery.
This post while whole in earnest may have been half in jest, so hopefully someone else with more knowledge of the range of mailers available will be able to help you out. Are you sending out a large volume of CD's to a lot of people?