This is one of my favorite humpback whale photos, I took it when we were "mobbed" by a few humpback whales on a boat in between the islands of Kauai and Niihau. They swam under the boat and would surface a few feet next to us. They surrounded us and basically forced us to stop moving for about an hour and a half.
They are massive, yet gentle. They were methodical but playful. You could feel their power, as they could have easy overturned our boat if they wanted to. Instead, they simply swam and surfaced and sang. We had an underwater microphone on the boat that picked up their vocalizations. It was one of the coolest things I have ever experienced in my life.