<img src="http://www.themeparkphotos.us/cpg140/albums/uploads/083107/J/IMG_9706.JPG" /> <img src="http://www.themeparkphotos.us/cpg140/albums/uploads/083107/J/IMG_9707.JPG" />
I don't think that's a chameleon.. The eyes are wrong, the feet are wrong.. It's probably a Basilisk Lizard, nicknamed the Jesus Lizard for it's ability to run on water I'm not 100% certain of my ID.. your critter looks a bit different than what I'm used to as the typical Basilisk shape, but the striking coloration plus the pronounced crest over the head and back are what I think of as Basilisk recognition features. The picture I referenced up there even shows the smaller secondary crest on the head that yours has. On the other hand, the recognition features for chameleons are the unusual eyes, and the feet with toes that have been fused into two large digits. http://en.wikipedia.org/wiki/Chameleon