SexyLightBox is a clone of the classic lightbox, but it is more lightweight and it looks sexier. It was built for web designers, so it is really easy to install and use. SexyLightBox supports all sorts of images of different sizes and HTML elements. The images larger than the browser, are adjusted automatically to see them completely. I really like the bouncy effect when the box comes out and resizes.

Requirements: Mootools Framework 1.2
Demo: http://www.coders.me/ejemplos/sexy-lightbox-2/
License: MIT License