If you frequent the DailyWTF site (http://www.thedailywtf.com), you've probably come across posts by Remy Porter, who usually (always?) includes HTML comments in his articles, and adds code so that when you click on a certain word, something magical happens.
This Alfred workflow, when run, shows those comments and highlights the clickable word.
I take no credit for the JavaScript code that does this, although I did tweak it a little bit.
Currently only works with Google Chrome.