A flexible jQuery plugin for conditional actions (like showing and hiding elements, triggering events or whatever else you need) based on values of one or many fields. This is an improved version of conditionize.js jQuery plugin. Unlike the previous version, conditionize2.js is not restricted to only show and hide actions. But for simpler migration from conditionize.js to conditionize2.js, show/hide is the default behaviour.
A lot of EXAMPLES available here.
A jQuery plugin to facilitate the handling of form field dependencies. Demo.