TinyMCE QuickLink button
The QuickLink button can be added to your TinyMCE toolbar to enable a user to create a link to the single content item selected in the tree. If the active tree is not the content tree or if zero or more than one item are selected, no link is created. When no text is selected in the editor, the item title is used as inner text for the created link.
Add the button to your toolbar in the tinymce config xml: