Brandon Aaron : Special Events
http://brandonaaron.net/blog/2009/03/26/special-events

jQuery, since 1.2.2, has had an API for “special events”. These events are special because they have the ability to do some extra work for specific events and even the option to bypass some of the internal jQuery event system. With these special events you can create custom events that require some setup work or you can completely overwrite the behavior of native events.

Rundown of the Special Events feature in jQuery edge