Unverse is a lightweight - absolutely tiny(about 5k) - collection of terse cross-browser JavaScript functions that perform common tasks. Even if used only for its lightbox feature it is probably the smallest JavaScript light box you will find.

Top level functions include:

• Lightbox pop-up for images, html, web pages
• Dropdown menu support
• Drag and drop - make any element draggagble and get notified of where it's dropped
• AJAX - one line asynchronous calls to server to populate parts of a web page
• DOM Ready - start executing javascript without waiting for images and other heavy page elements to load

It also provides lots of cross-browser JavaScript short cuts to show and hide elements, get items from the DOM, get values from form fields, enquire on window dimensions and populate elements using AJAX.

Demonstration at http://unverse.net