Burj Dubai at the Cityscape Abu Dhabi 2008 the rad models are wind tunnel models to test the behaviour of the wind on the towers. They are packed full with electronics and other stuff so therefore really expensive.
The Burj Dubai (Arabic: برج دبي "Dubai Tower") is a super tall skyscraper currently under construction in Dubai, United Arab Emirates. When it is completed in 2009, it will be the tallest man-made structure in the world. Scheduled for occupancy in September 2009, the building is part of a 2 km² (0.8 sq mi) development called Downtown Dubai.