"Play GIF" for control of animated GIFs

A Reddit thread about U.S. population growth 1950-2010 displayed the "baby boom" bubble using a rather slow animated GIF.  The top-rated comment then provided a link to "Play GIF," a website that allows you to control the animation of a GIF.

Here's an example using the Chinese population 1950-2050.

Note that you can pause the animation, speed it, slow it, reverse it, or have it play forward-and-back.

Here's the homepage, where you can plug in an animated GIF of your choice and see what happens.  I suspect those viewing adult GIFs will be early adopters.