Have you ever seen a website where banners dinamically change on the page, no matter you browse the pages or no?  Now this mod will allow you to do the same, add as may banners site wide to any section, and turn the rotator mod in admin panel and all your banners will start exchanging on your website with ajax, that means without refreshing the page.  All you have to do is set the interval how fast the banners has to be exchanged.