Yes as the punchline says… “The missing UI library for the Web” – jQuery Tools provides some missing libraries like the tooltip which i like the most along with the dynamic positioning. It also provides gorgeous looking Tabs, scrollable slider, Form and other toolbox for history and other needs. check out http://flowplayer.org/tools/index.html .
But i think still jQuery is missing many other libraries which a front end developer would like to have.
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