This is only an example, so you have to edit it to fit your own needs:
First make a new template (examplename: skyscraper):
Put the following content in it:
HTML Code:
<style>
.skywrapper {
position: relative;
width: {vb:stylevar wrapper_max_width};
margin: auto;
}
.skyscraper {
position: absolute;
right: 0px;
margin-right: -160px;
}
@media only screen and (max-width:1520px) {
.skywrapper {
display:none;
}
}
</style>
<div class="skywrapper">
<div class="skyscraper"><img src="/images/skyscraper.png"></div>
</div>
Second, create a hook for your template and choose the template-hook "header_before_notices".
If your forum wrapper have a 1200px max-width and your skyscraper have a 160px witdh it should work now. If not you have to edit @media only [wrapper-width + (skyscraper-width * 2)]
In my example 1520px = 1200 wrapper and 160px skyscraper * 2
Thats it!
If you have a full width forum you should use a 3 column-layout.
Would be nice to see you at my forum, there are some other add-ons, exapmles...