Changing from Prototype to jQuery, equalvent of creating a class to encapsulate functionality

Changing from Prototype to jQuery, equalvent of creating a class to encapsulate functionality

Hi all,
  I'm writing a widget using jGrowl.  I need this widget to periodically poll the server and queue new messages into the jGrowl message queue.  This itself is pretty straight forward.  In prototype, I'd simply create a controller class that hits a JSON service, then parses the response and queue's up the messages.  I'm having a hard time finding anything like "jQuery for Prototype users".  Does anyone know of any good example on how to cleanly encapsulate this functionality in jQuery similar to a class in Prototype?

Thanks,
Todd