Paco Jimenez Franco is the captain of a whale watching boat off Baja California, and has been for twenty years. It stands to reason that the whales have come to know him, and better yet, trust him. Occasionally, a whale will come close enough to the boat for Franco to touch it, and he will take the opportunity to pick off any whale lice he can reach. These are crustaceans that attached themselves to the whale's skin. Recently, a whale who got this treatment came back again and again for Franco to pick more off! The same whale has approached Franco on subsequent outings.
Franco said he's done this for other whales and has gotten the same reaction. While environmentalists normally frown on human interaction with whales, it's different when the whale initiates the interaction, and when it's beneficial to the whales. -via Everlasting Blort