Ooops, the commentary on Jester's Digs. This is made with 40 by 10 elements staggered on each layer all of stone. Try any weapon and watch the castle fall apart piece by piece! My personal favourite was the metal stones as it wore down the castle. Time bombs were cool as well!
The interesting part is that there is very little lag due to the offset of the horizontal pieces. I may try something a bit more elaborate in the future.