If i have a 3colum-all fluid
mainleft, maincenter, main right.
Not 100% sure what your asking but I think this is what your after.
Use an include for the nav.
PHP if you got support for it.
SSI if you got support for it.
like if i re-designed my site to look like this
i trying to see how a link would open, rather than having a link open a page and replace the entire page. this way one page would need the menu, and open them in the other parts of the page
hope that makes sense
You could do something pretty similar using an iframe with the border set to 0, and scrollbars disabled if you didn't want them. This way it would look like one page but you wouldn't have to load the menu each time. The only problem would be users bookmarking pages.