A Singleton UI Widget. I wonder if this is a sane approach?

gistfile1.js

// a ui dialog that can only appear one at a time uses jquery dialog
Widgets.UI = function() {
  //gather the dom elements that made up the UI
  var dialog = $('#dialog'),
  linkTargetField = dialog.find("#link-target"),
  saveBotton = dialog.find('#save'),
  //changing state
  node = undefined;
  
 //event handler 
 saveBotton.click(function() {
    node.attr('href', linkTargetField.val());
    dialog.dialog('close')
  });
  
 // singleton to set state and open dialog.
 return Widgets.UI || function($node) {
    linkTargetField.val($node.attr('href'));
    node = $node;
    dialog.dialog({modal: true});
  }
//calling initialization directly
}();

//usage
Widgets.UI($("#link"));

widget.html

<div id="dialog" style="display:none">
    <label for="link-target">Link URL</label>
    <input type="text" id="link-target" placeholder="http://example.com/">
    <input type="button" value="Done" id="save">
</div>