There's a
huge cave on the north shore of Kauai that is used by surfers and beach bums as a place to camp/live. At least, they used to camp there several years ago when we visited on our honeymoon. It had a nice comfortable sandy floor and was very large. Not a bad life. Surf all day and then go sleep in a cave on a warm tropical island. Place was large enough that you could walk around in it while others were living there, and you wouldn't bug each other. About the size of a football field. Pretty dark though in the back of the cave.