Eternal Moonwalk is a jaw-droppingly fantastic idea, and is one of those reasons why I absolutely love the Internet.
On seeing it for the first time, I uttered "Holy crap that's awesome." I suspect most everyone does this, on seeing the site for the first time.
Users are invited to submit a video of themsemves (up to 10 seconds in length) performing Michael Jackson's classic moonwalk, from the right of the screen to the left. These videos are randomly stitched together, to make the appearance that one person moonwalks/morphs into the video following. To top things off, there's a small counter at the top that follows each video, letting you know the total distance that's been moonwalked during your view.
It's a great concept, and incredibly well executed. It's both playful, and a fitting tribute - and pulls off both really quite well.
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