I am looking for a song with a guy singing the whole room joins up, each singing their own part.?

I think it was on CollegeHumor a few years ago (could be cerca 2004), and involves something like a classroom or an office. There are over 50 people in the video and the camera is just one big take and one big choregraphy.
I am looking for a song with a guy singing the whole room joins up, each singing their own part.?
its the prison in the phillipines where they do michael jackson choreographed. its kinda funny but disturbing. www.youtube.com
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