Hi Stephan, the script I'm using is called jzoomit.min.js, I've used it on two sites.
This is what's in the head of the file:
/* jzoomit.js * v1.0
Copyright (c) 2010, Victor Soroka, http://www.jzoomit.com
Liscensed under the MIT License (http://www.jzoomit.com/MIT-LICENSE.txt)
but jzoomit.com no longer exists, which is odd. Does the 'MIT License' mean it isn't open source (or whatever the phrase is)?