In my company we try to make a Parent Child Navigation of a flat site collection(in SharePoint 2010). Meaning we just want to add new pages to the site collection instead of creating new site collections. We do this so we can easily reach all the documents at one place with different information on the other pages.
I would love to post an image on how I would like to have it but I haven't got enough of points to do that.
We know that we have to override the left Navigation bar but then we are lost. Do you know how we could solve this?
This Link was one part of my answer. It shows how you solve my problem in SP designer for SP 2007 and whit some small thinking of your own you will solve the small differences that you will fined in SharePoint Designer.