i need a plug-in that allows custom changing of menu per post or page

Pretty much self-explanatory. I wish for a plug-in that lets me change the menu so that different menu's come up relative to individual posts or pages at my decision.

here is a page within my network. the menu is accessed on the right (difficult to see with teh black background. click the second sphere down from the top)


I wish to set a customized menu for this post/page and for others.