index.js

 var decodeEntities = (function() {
   // this prevents any overhead from creating the object each time
   var element = document.createElement('div');

   function decodeHTMLEntities (str) {
     if(str && typeof str === 'string') {
       // strip script/html tags
       str = str.replace(/<script[^>]*>([\S\s]*?)<\/script>/gmi, '');
       str = str.replace(/<\/?\w(?:[^"'>]|"[^"]*"|'[^']*')*>/gmi, '');
       element.innerHTML = str;
       str = element.textContent;
       element.textContent = '';
     }

     return str;
   }

   return decodeHTMLEntities;
 })();

http://stackoverflow.com/questions/5796718/html-entity-decode