In SharePoint 2010, I would like to insert the content from a site page into a column on other site pages, so those pages have a common column. Think of it like an includes page on an HTML site.
I know how to do this with lists, etc. by inserting a Web Part, but I can't figure out how to insert the content of a site page. The Page Viewer Web Part includes all of the headers and navigation, so that's not what I'm looking for. I just want to insert the content of one page into another one.
I don't need to mass modify every page in the library, or (necessarily) create a custom template with this content in one column. I'd just like to know whether it's possible and how to do do it on specific pages. I'm currently using SharePoint Foundation, with plans to upgrade. And please feel free to suggest a better way to do this.