Command Tasks have always been one of the most popular styles of team building events. These are the tasks such as building a bridge using barrels and planks and crossing a minefield, a grid of squares, through the one safe path without talking. They are good team building activities because they can be done in 20 minutes and what happened is clear and can be discussed. Teams rarely have this sort of opportunity in their work tasks.
These challenges evolved with the popularity of the TV show The Crystal Maze and there are now many more challenges which are run in a format like the show. The tasks themselves have become more sophisticated and there is even a dome that can be hired in for the grand finale.
We have excellent Command Tasks and a Crystal Challenge format. It is very popular and counts for a good half of all the events we do. It fits the times because companies want to have fun but they also want something with team building benefits.