BioniX Wallpaper is the program that allows you to change your background wallpapers at any chosen time interval, from 1 second to days. It is a shareware wallpaper rotation application that's advanced and easy-to-use.
Here are some screenshots to illustrate the features and user interface of this application:
Bing Wallpaper
Lively Wallpaper
DisplayFusion
John's Background Switcher
Kiwi Random Wallpaper