JSON format became quite a standard format for data exchange. Its simple syntax, JavaScript compatibility and human readability are probably the reasons for its wide adoption.
This plugin has a very nice visual editor for customizing the JSON data and a visualizer that provides a different view for it.
Mosaiqy is a jQuery plugin for viewing and zooming photo working on Opera 9+, Firefox 3.6+, Safari 3.2+, Chrome and IE7+. Photos are retrieved from a JSON/JSONP data structure and randomly moved inside the grid. All expensive animations are taken over by your GPU on recent browsers using CSS3 transitions, minimizing the CPU overhead.