My favourite art is the type that takes you by surprise, you find it where you least expect it, out doors preferred. Knowing someone was inspired to do something and they did it and they left to for the people to enjoy, no permission, no fanfare, no worries.
Some may call it folk art, but use what you got, and have a good time making it, and leave it for the public to discover. Forget galleries or trying to make money from it, just do it and move on and leave the world with something to ponder.
These little rock sculptures were found on the rocks below the car park near the surf spot called The wreck in Byron Bay, I love to run into these types of oddities, puts a smile on my face, art for arts sake.