SharePoint user control to display a random image

The master page of a SharePoint site I work on loaded 7 photographic images, all over 50 kB each, to display at random as a banner adjacent to the site logo. The way it loaded the images was very inefficient: a default image was loaded in the HTML, and Javascript on the page created 7 image objects and returned one at random to overwrite the default. I decided to find a C# way to solve the problem.
Continue reading SharePoint user control to display a random image