Grand Central Terminal is a cool place. So cool, in fact, that it attracts an estimated 21,000,000 annual visitors (okay, so maybe some of those people are actually commuters) and this year marks it's 100th anniversary. To celebrate, the MTA Arts for Transit organization teamed up with the Improv Everywhere improvisation troupe to stage an LED light show-flash mob. 135 seemingly ordinary commuters and spectators were on-hand, gracing the windows of the Terminal along Vanderbilt Ave. flashing white, red, green, and blinking lights followed by an impromptu dance solo.

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[via MTA Arts for Transit]