Animating A Single Item Using ngRepeat And ngAnimate In AngularJS

It's easy to think about animations when you have objects that have conditional existence. Meaning, sometimes they're on the page, sometimes they're not. But, what about when you have data that is always present, but is sometimes changing? How can you animate that? One idea would be to create a custom directive that watches the data and leverages the $animate service explicitly. But, it turns out, with a funky hack, of sorts, you can use the native ngRepeat directive to animate changes within a single object reference.