MacZIP is a complete port of the Info Zip ZIPping and UNZIPping utilities for the Macintosh that supports encrypted archives. It has a very simple interface and supports Apple Events, and full source code is available.
The "Crypt" version includes encryption code that was originally written in Europe and can be freely distributed from any country except the U.S. If this code is imported into the U.S., it may not be re-exported from the U.S. to another country.
Can't find what you're looking for? Try a search:
Also, if you have an older Mac, be sure to check out the "Classic" applications page for more options.
Finally, take a look at ALEMIA if you think you know that name of an application, but aren't quite sure.
No, I don't accept reviews anymore for these older applications. With the creation of this page in the Orchard's late 2005 redesign, I only accept reviews for currently-developed applications that work on Mac OS X (or later....whatever that might be!!).