Fixed div when scrolling an html document

Im looking for a jquery plugin that lets me do this effect: static scrolldown

Scroll down... you will notice that the block at the left always stays fixed -attached 开发者_运维百科to the top. Any ideas? I don't know where to start searching.

Thanks.

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check out this blog post on the technique:

http://www.massless.org/?archive=2008/12/pegs-experiment-in-page-layout-and

includes a demo, should be enough to get you started