I've looked around at the orgmode and org babel manuals, and I am still not sure that I want to do is possible...

I have an HTML file that is an e-mail signature that I use. Up to now I've had copies of the HTML in couple of template ORG files, like so:

#+BEGIN_HTML

<div>

signature and corporate disclamer stuff

</div>

#+END_HTML

This has been working, but again, I have the exact same HTML copied in 5 different files, which means 5 separate edits for any changes.

I just tried:

#+BEGIN_HTML

#+END_HTML

but getting the CSS right has been challenging.

Is there any way to make orgmode insert a the contents of file during export?

Thank you,

Zach