Below, you'll find an example of a rotating billboard showing three different images created using only CSS3. Feel free to dig in the code (or read the article) to find out how it works.
Take note this example only fully works in Safari and Safari Mobile for iOS. Although the animation plays in Chrome (which also is a webkit browser), it doesn't support all the CSS properties (yet) that are used.
The billboard outline is created by Codrops, who created this sort of effect with jQuery.