4sqDay 2012 is a Foursquare celebration with Meetup events planned worldwide. The fun happens on Monday April 16, 2012. If you are interesting in participating, join a meetup (or host one) and use the 4sqDay logo on all your related party items. Here’s some tips on how to plan a great event. The story behind 4sqDay is a good one, take a look.
…The thought struck [Nate Bonilla-Warford] that since four-squared equals 16, it would be great to check into Foursquare on the 4th 16th of the year, otherwise known as 4 / 16 or April 16th.