Bukkit plugin that makes buildings fall over
The basic commands are:
createfall <name>: Gives a wand to select the "building" to make fall over
deletefall <name>: Deletes the fall selection
startfall <name>: Makes the building fall over
stopfall <name>: Stops a running fall
resetfall <name>: Resets the building to before the fall took place
The challenging part of this plugin was the math to rotate the building as it fell. At the time, I had not taken any 3D trigonometry or linear algebra so the math behind making a 3D rectangle rotate in real time took a while to get my head around.