I was using an implementation of my BounceBox mootools javascript class on a site I am working on at the moment, and made a couple of additions to the Class that I hope other will enjoy.
The new version1.1 demo can be viewed at http://bouncebox.lendrum.co.nz/ and the change log with a new version 1.1 demo link at the bottom of that page to show full screen positioning that is now supported.
The Demo page has full links to download this free Mootools Javascript effects class.