[Max Taxable]

I did this, for mobile but works great for regular styles as well. Single image, scaling header:

In header template put:

<a name="top"></a>
<td valign="top" style="padding: 0pt;"><table width="100%" border="0" align="center" cellpadding="0" cellspacing="0">
<td align="center"><a href="./"><img class="imageObject" alt="Your Forum Name" src="http://yoursite.com/images/misc/yourbannerimage.jpg" width="100%" height="100%" border="0" align="center" /></TD></table>

Then in extra CSS attributes, define the img class for IE compliance: (This is a MUST.)

.imageObject {
max-width: 100%;
}

This insures the single header image will scale both in width and height and keep perspective.

Examples where I have implemented this:

MLB Fan Forum - Powered by Baseball Fans

The Dallas Cowboys Forums - Dallas Cowboys Fan Forum Mobile Style

US Messageboards - Opinion, News and Information

You can see the header image on those sites adjusts to your browser width. As you make it skinny, or wide, it moves like a 3 piece header would but it is just one image that scales. (However this is impossible to accomplish for chrome and safari, they ignore the 'max-width' definition.)

BEST RESULTS: Make your banner image at least twice as wide as the widest mobile resolution you would encounter (maybe 700px wide by whatever the height is) so that you are always only scaling down, not up. For better quality.