One of the most powerful scripts that should be in every webmasters toolbox. So simple and fast to set-up, you'll hardly believe it. A "URL Rotator" is by far one of the best marketing tools on the internet today.
The basic principle is to create a rotator portal and place several different url's (website pages) into the portal. Then everytime someone visits the portal page the urls will be rotated and the visitor will be transparently redirected to the next url in the list. You then only have to promote one page/url (the portal), rather than many!
