The second TEDxBuenosAires event on "The Revolution of Ideas" was held on April 8 at the La Rural community center in the heart of Buenos Aires.

Over a thousand people attended the event and enjoyed speakers such as Argentine rugby player Agustin Pichot and musicologist Marcelo Arce.

Those who could not get a ticket to the venue did not have to worry about missing the show --  the entire event was live streamed online, and also projected on two giant screens in the city, located in the Plaza San Martín and the Villa 31. Plaza San Martín is a green public space in Retiro which has a traffic of about a million people daily.  Villa 31 is a shantytown also in Retiro, home to about seventy thousand people.

A banner placed under the screens read "Inspiration and knowledge are not just for the elite." 

At TEDxWaterloo in Ontario, Canada -- which took place on March 3rd, 2011 -- attendees found themselves face-to-face with a “Tower of Tweets." 

Five Christie MicroTiles --  world-famous digital projection screens -- were stacked atop one another to form a column in the venue’s lobby.  Taking this technology, Patrick Dinnen of Media Lab Toronto designed a custom Twitter wall that pulled and displayed all tweets with the #TEDxWaterloo hashtag tweeted during the event. He wanted to create an easy way to view virtual conversations in the real world:

Here's a short video of Dinnen's "Tower of Tweets" in action.

For more information on TEDxWaterloo, visit their website, Facebook page and follow them on Twitter.