This page features two examples: a regular Purr and a "sticky" Purr. Clicking the links below will present a new Purr each time. Notice the relationship between the sticky and regular Purrs. Only the top non-sticky Purr in the list is removed at a time.
These notices also feature the usingTransparentPNG parameter. If you are viewing this page in IE7, you aren't seeing the fading animations.
The information icon is courtesy of MouseRunner.com.