Japanese contractors, Kajima, have created a new system for imploding high buildings from the bottom up. The process is to install giant hydraulic jacks on the first floor, manually demolish all the building material on that floor, then lower the jacks a second floor and repeat the process.
This system is called daruma-otoshi, which is the name of a popular Japanese game were the concept was taken from. Pink Tentacle says:
According to Kajima, the daruma-otoshi demolition method — which is now being used to dismantle a 75 meter (246 ft) tall, 20-story building and a 65 meter (213 ft) tall, 17-story building — is safer and creates less noise and dust pollution because the work is kept close to the ground. In addition, this method cuts demolition time by 20% and makes it easier to separate and recycle the building materials.