From London to Moscow to New York, Chicago, Dubai and Shanghai, almost every single high rise city in the world is seeing skyscraper projects canceled even as they have their foundations laid and start to rise from the ground.Here is a list of the biggest projects that have been put on hold so far. The disappointing reality is that almost none of them have any particular architectural merit, apart from Calatrava's Chicago Spire, perhaps, and reflect a period when architecture firms were too overloaded with work to think very hard about the designs. Vote for which ones you would have liked to have seen finished.