Check out this very modern take on the trebuchet.
Historically the trebuchet was the weapon of choice in any siege, providing the ability to launch a variety of projectiles at enemies and their fortifications from a large distance. From huge stones used to destroy city walls and crush soldiers, to human corpses used to break morale and spread disease, almost anything could be hurled.
There are many designs of trebuchet but the majority normally fall into two categories, traction or counterweight, the latter coming to prominence in the 12th century Crusades.