Using a dropdown box to change PHP include() value

Hey guys,

I am building a simple page with two drop down boxes, I was going to have each load in html documents into an IFrame on the same page, but I have seen that the PHP include() does the same thing and works on my server.

I was wondering if it was possible to have the dropdown box change the include() value when selected to load in a new html document into the same page while keeping the top banner and drop down boxes in place.

Cheers.