Java support in some browsers has been discontinued. To run Mocha without a browser, make sure you have a recent version of Java installed. Open a command prompt and type the following:

javaws http://www.haplessgenius.com/mocha/mocha.jnlp

You must agree to run Mocha at the Java security prompt because this version can load and save cassette, disk images and snapshots locally. If there's any interest, I may create a standalone jar file.

Miscellaneous

Original Mocha Web Page - If your browser still supports applets.
What's New? - List of changes over the years.
E-Mail - Let me know what you think. Bug reports and suggestions welcome.

The Future

Android Version - This actually exists although it remains unfinished.
JavaScript Version - So I can hang with the kids.