Well, that is what the Guardian calls it. They say that the new stadium proposed for the 2012 Olympics is being designed to be demountable, so that it can be sold after the games. They note also that it could be "the first step in a new approach to the games, which could become more like a travelling circus to keep costs down and allow poorer countries to play host."
London is talking to possible 2016 host Chicago because "both cities have decided to build main stadiums with small numbers of permanent seats while erecting giant seating scaffolds for the two weeks of competition. Talks have focused on how London's stadium might be bolted rather than welded together, ensuring the materials used allow it to function properly in another country and climate, and how sections might fit on a cargo ship."
The Guardian continues:
It would be the first time in history that a stadium of this size has been moved. Last year, 16,000 seats which had previously been used at the 2006 football World Cup in Germany were shipped to Barbados where they were used in the ICC Cricket World Cup. "If we could box it up and ship it to the next games, that's something that could benefit the Olympic movement," said Doug Arnott, director of sports and operations at Chicago 2016. "We have had preliminary discussions about what London's stadium design team are planning and how it might fit in. This is to do with the responsible use of materials and trying to avoid leaving infrastructure that will burden a city."
HOK Sport, architects of London's Olympic stadium, have deliberately designed the arena as a kit in part. A permanent concrete bowl of 25,000 seats will remain in place for athletics, lower league football and rugby, but every other component could be sold on. Chicago has made staging a low-impact games a core part of its bid. It is using several existing arenas, including Soldier Field where the Chicago Bears NFL team play, and the Chicago Bulls' basketball arena will host gymnastics and basketball. "Chicago think this would be a coup for their bid, and would show they are putting their money where their mouth is on their commitment to sustainability," said a source. ::Guardian