eliminate the need for multiple sidebars create complex logical statements with conditional tags to control widget’s visibility 25 conditional tags, 11 with additional options or, and, not logical operators works with any custom or built-in widget no code editing intuitive and simple drag-n-drop GUI extensive in-line help has much more options and it’s easier to use than Widget Logic
Online demo, examples and documentation
Changelog
v1.4 - December 13th 2012 * WP 3.5 update
v1.3 - March 6th 2012 * 2 new tags: is_tax() and is_user_role() * few minor bug fixes
v1.2 - June 4th 2011 * significant speed improvement in admin GUI when working with a lot of widgets (+20) * few minor bug fixes
v1.1 - June 2nd 2011 * new conditional tag: is_user_guest * prevented AJAX requests caching (in admin)
v1.0 - June 1th 2011 * initial release
Note: Widget Ninja can only control widgets that use Widget API and not the ones that use deprecated register_sidebar_widget function.