A Javascript accordion script is powerful and lightweight at only 1.4kb. It includes multi-level support, the option to allow multiple panels to expand concurrently, and a hide/show all toggle. Its now updated with DIV based structure.
Compatibility: All major browsers.
Website: http://www.leigeber.com/2009/03/accordion/
Demo: http://sandbox.leigeber.com/javascript-accordion/index.html
