I need to add a banner for my host that can be viewed on every page, without having to scroll down. How would I go about adding a dynamic banner?

Something like this! Except a banner in that place!

At this point, I've got the banner completely above the theme, sitting as far to the top of the page as it will sit. I would like to move the banner to the space to the right of the logo, or somewhere in the body, if possible, again, like in the same spot this site has the banner.