I am trying to achieve this in HTML/CSS:

```
+---------------------------------------------------------------------+
| HEADER DIV                                                          |
+------------+--------------------------------------------------------+
|            |                                                        |
|            |                                                        |
|            |                                                        |
|            |                                                        |
|            |                                                        |
|    nav DIV |   scrollable DIV                                       |
|            |                                                        |
|            |                                                        |
|            |                                                        |
|            |                                                        |
|            |                                                        |
|            |                                                        |
+---------------------------------------------------------------------+
| FOOTER DIV                                                          |
+---------------------------------------------------------------------+

```

* Header and footer div are browser window width.
* header and footer and fixed height in pixels
* header and footer and fixed on the top and bottom of the browser
window nav div is the height of the browser window minus (header height +
footer height)
* scrollable content is scrolling internally, without affecting the
absolute position of hte footer or header.

I can only get to a point where both nav DIV + and scrollable DIV scroll together.
I can't make the NAV div not scroll while the scrollable DIV scrolls. 

I guess the key is how I put the two divs side by side and yet not scroll one of them when the other scrolls.