Not the actual toy, but the interlocking and standard size ideas applied to real world training grounds:
Over the last five years, the U.S. Marine Corps has built the world’s largest urban warfare training area at their 29 Palms base out in the Mohave Desert of California. There are currently some 400 structures, from private homes, to large government building complexes, operational in the training area. When development of the center is complete, there will be over 1,200 structures to train in.
[. . .]
Many of the buildings are really shipping containers, equipped with doors, windows, some paint and contents, are being used to represent the buildings. Like Legos, the containers can be joined together, or stacked, to make larger buildings. More importantly, the entire “town” can be rearranged to represent a different kind of environment. The training towns now being built represent what the marines are currently encountering in Afghanistan. But in a few years, the marines may be fighting somewhere else, and they want their training town to reflect that, quickly, when the need arises.