JCR Links Extensions..
Imagine you have 5 Different components and they all come with their own custom registration Links. You don't want your users to click on the core joomla registration link which usually resides under a login module which is usually the case, you'll want to put them all together in an article and do a hack to hide the core joomla registration link.
JCRLinks is a plugin that helps you link your core joomla registration link to an article which will consist of the different services, so, your users won't make the mistake of clicking on the wrong registration link.
JCRLinks also gives you the option of hiding registration link whenever a user is logged in.