Theme Switcher Reloaded plugin by Themebot allows the viewer to make a selection from available themes and it does it well. This plugin is being used on our website ( see the sidebar ).

What if you have more themes installed than you want to allow viewers to choose from? There is nothing in documentation of the plugin to explain it. Here is a simple solution:

Add one line:
 
    Status: unpublished
 
to the header of style.css for each theme which should not be available for selection.
 
Note: remember to select in your widget 'full name (default option)' as a method of displaying theme names!
 
That's all!