Script for menu

I want to create a menu like the left (as we see that) menu of getitnow.gr.
Do you know any script for this?
I use prototype framework,is there any script related with prototype?
Thank you

[edit:]I mean a script that make the menu to stay even we use the scrollbar of the brownser.

I found these scripts.
http://www.javascriptkit.com/script/script2/staticmenu.shtml
http://www.dynamicdrive.com/dynamicindex1/staticmenu3.htm