If you configure your Java VM to load some of the Java Accessibility Utilities - specifically Ferret or Monkey, and specifically NOT JavaMonitor - and then use appletviewer to load an AWT or Swing applet (e.g. http://www.ndr2.de/chat or SwingSet2.html), you will not be able to use the mouse or spacebar to activate the buttons, toolbar buttons, or most other UI elements (menus work though).