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Confluence uses this one - http://fancybox.net/
Modified with long captions - http://labs.abeautifulsite.net/projects/js/jquery/fancyBoxCaptions/demo/
Comparison and refinement chart - http://planetozh.com/projects/lightbox-clones/
This is a close alternative thought I find it does not look as nice - http://www.nickstakenburg.com/projects/lightview/
This one comes up a lot - http://colorpowered.com/colorbox/
!!!! jQuery TOOLS - has lightbox effect and more... looks more well thought out too http://flowplayer.org/tools/demos/index.html
Neat effect for annotations overlays - http://tympanus.net/Tutorials/AnnotationOverlayEffect/
Maybe use for Myra's website to show hover on projecs... but it should be reversed not lowered - http://www.sohtanaka.com/web-design/examples/hover-over-trick/