Some of the giant vines in the video game I am working on. These vines are "animated" in game through a "magnetic" force. The vines are rigged and have rigidbodies placed on their joints. The end vine joint also has a script on it that is attracted to a corresponding script/force which happens to be on the player so when the player runs near a vine the vine will dynamically chase after the player. This allows for some interesting gameplay interactions and some nice overlap and follow through.
The magnetism is thanks to a simple, physics toolkit on the Unity Asset Store.
The vines are also setup to use PuppetMaster to ragdoll the player.