Casually checking out my Tweets and Peter Elst put this link up: http://www.coreyoneil.com/portfolio/index.php?project=5
It is very difficult to perform collision detection. Usually, sometimes you need some kind of mathematical algorithm to carry it out. But Corey managed to do it at a pixel level and even at on gradient / alpha thresholds. Very impressive indeed! It’s funny to see the Stephen Colbert video. Highly recommended blog reading!