Tiller Man
The Tiller Man is the NPC that lives on a Boat and sails it, following orders spoken by players. He will always obey the orders of the player holding the boat key, or the closest player. A tiller man will not assist in combat against sea creatures or with other ocean-going perils. He will sometimes yell out warnings if turbulent waters are encountered on a server line.
By double-clicking the tiller man, a player holding the boat key may rename the boat. Other players doing so whil not holding the key may endure his salty wrath. The tiller man also displays the condition of the boat.
If a course is laid out on a map, it can be dropped on the tiller man so he knows what path to sail.
In times past, tiller men would relate tall stories of the seas, but have been silent these past few years.
Update March 20, 2010: The tiller men are once again regaling passengers with fancy tales.