Jquery plug-in-5 small plug-ins

The best thing about jquery is its convenient plug-in mechanism. Many people contribute useful plug-ins on the Internet, but there are too many plug-ins. It may be difficult for unfamiliar friends to choose from. I think it is necessary to publish this post to collect some commonly used plug-ins. It is best to make some comments for others' reference.
I will first list some of my frequently used ones. Please add them. This post aims to inspire others.

Ifixpng:
It is convenient to modify that IE 6.0 does not support transparent PNG images. It can be used for and PNG as background elements, as long as $ ("selector"). ifixpng.

Easydrag:
Simple drag function implementation. It is much simpler than the interface plug-in. You can refer to this plug-in for customization if you have high requirements on drag. I have slightly modified this plug-in. I have introduced it in two posts (Extended jquery plug-in easy drag, floating window drag (continued )).

Background IFRAME:
It is also an essential plug-in for home travel. It is used to effectively block other elements in IE 6.0 <select/>.

Tooltip:
Display a nice tooltip (you can use CSS to customize the style ).

Contextmenu (right-click menu ):
Easy to use and customizable styles, but multi-level menus are not supported currently.