How to implement a floating and drag-able panel

I wanted to implement a floating and drag-able panel, where all the html and css is place inside a div tag, then use JavaScript to trigger the drag-able effect.

Here is the similar references I found of, but I looking for better approach.

http://www.quackit.com/css/codes/css_floating_menu.cfm

http://www.fiendish.demon.co.uk/html/javascript/layerfl开发者_JS百科oat.html

http://net.tutsplus.com/tutorials/html-css-techniques/creating-a-floating-html-menu-using-jquery-and-css/

any suggestions or advises are welcome, thank you in advanced.

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http://jqueryui.com/demos/draggable/