i was told by an old buddy hongerdude aka ~PA~Ihateuall~ that if you right click on a building in the back of a base and have the saps highlighted and hit an F key they will blow up automatically and hit big buildings. i dont remember what exactly it was so i couldnt try it but if its true i know axo or kith knows. is this true? how? =]

You have to line them up well enough so that they wont destroy each other. Target a farm in the back of his base someplace. As soon as the first dwarf hits the farm, it will destroy it, and the rest of the dwarves will blow up, destroying anything around them.

I'll be putting up a cute little sapper trick in useless facts in the next few days.