Temporary/securely Preview your site with different(Test) themes. After activation, enter "Settings>Theme Test".
Contact Form 7 - Different Custom Error Messages for each field tags.
DS adds functionality to display different widgets in a sidebar, according to a context (for example, a specific page).
Simple , minimalistic plugin that lets you set different locale for frontend and backend.
Create Parents / Children Relationship between different post types checking one or more parent.
The very first plugin to style your menu list or page listing items differently. ( i.e. custom icons for each menu! )