I just recently updated my install of the NextGen Gallery,
while doing so, i had a vision of inspiration, for using the gallery slide show feature as a rotating header banner image for one of the sites ive been working on,
Created a new gallery, uploaded the banner images,
created a new sidebar widget('header_images'), added a slide show
with a fixed width and height to it, along with the gallery i wanted to use, and exclude all other galleries,
In my header.php file for the template, were the header banners used to load, i replaced that with the function code to check for a widget, and bobs your uncle ive got a rotating header, with nice image changing effects :)
the gallery idea can be seen here..