Code used in screencast http://www.youtube.com/watch?v=3_1hfIi3p6E

taggable-server.js

// Make all elements with the class 'photo' into a taggable object 
$('.photo').taggable({
  tags: '#tags .tag.active',
  tagged: onTag ,
  untagged: onUntag
});

/**
*  Handler for the 'tag' event. When this fires, 
*  this handler will send the tag data to 
*  the server along with the id of the image 
*/
function onTag(element, tag){ 
  // If the tag doesn't 'already exists here...
  if( $(element).siblings('[rel='+tag+']').length == 0 ){
    /* Graphically let user know tag was added */
    $(element).after('<div class="tag active" rel="'+ tag +'">' + 
      tag + '<div class="close control" /></div>');

    // Send to server
    $.post(
      remoteURL, 
      { 'action':'tag', 'image': $(element).attr('rel'), 'tag':tag },
      function(results, txtStatus){ 
        console.log(results,txtStatus); 
      }) ;
		
  }else{
    // Give the user a hint
    $(element).siblings('[rel='+tag+']').effect('bounce');
  }
};

/**
*  Handler for the 'untag' event.
*/
function onUntag(element, tag){
  $.post(
    remoteURL, 
    { 'action':'untag', 'image': $(element).attr('rel'), 'tag':tag }
  );	
};