4D Cities is software that allows you to reconstruct cities analyzing data from a stack of old photographs. It also allows you to travel through the fourth dimension without a flux capacitator, showing buildings as they rise and fall in time. It has been developed by Frank Dellaert and Grant Schindler, from the Georgia Institute of Technology, and Sing Bing Kang, Microsoft Research Lab scientist. Demo video after the jump.
See a city change in four dimensions [New Scientist]