I'd like to display embedded YouTube videos with the controls hidden by default, and when the user clicks on the video, controls appear. Just as the videos on [this page](http://www.chrisspooner.com/).

In Google documentation pages I found how to hide controls altogether, but not in this way. And using Firebug while visiting this page I can't see any options used in the iframe code that relates to controls.

So how to do that?