Justin has made real Bielebers of the Twitterverse.

On Thursday, the movers and shakers of social media couldn’t resist, well, moving and shaking to the Bieber’s hit song “Baby.” Twitter employees flashmobbed their crowded cafeteria, showcasing a popping and locking male lead and a female employee who could rap the entire Ludacris section (we didn’t even think those were real words).

Twitter has said it was to celebrate #hackweek, but it was great timing — Bieber is poised to hit the 25 million Twitter followers milestone today. It would make him the second most followed person on Twitter, trailing only Lady Gaga’s more than 27 million followers.

Hackweek is a good excuse, but maybe all of Twitter-land just couldn’t contain their Bieber-fever any longer.

What’s your favorite flashmob YouTube video? Share with us in the comments.