Yes ... a harpist. And why not? It's a harmony producing instrument just like piano. The following is from an article on how to improvise for the Celtic Harp. I wanted you to see this because it's just as applicable for piano. Here's the article...
Learning to create a music improvisation on the Celtic harp is really easy. Not only that, but it is a skill that improves so many other areas of your harp playing. Here's an overview of what the simple practice of music improvisation can do for you:
~ Allow you to play anywhere, anytime, without music
~ Generate ideas you can use in arranging
~ Generate ideas you can use in composing your own music
~ Free you to respond completely to the person you're playing for
~ Allow you to play with many other musicians easily
~ Make playing the Celtic harp way more fun and easy
~ Teach you to be flexible and adapatable in life
There is a reason that music improvisation seems out of reach to many. Because of musical experiences in life that left us less than sure of our abilities and a culture that worships the few star musicians in any genre, most adult musicians (and especially beginners) believe they can't create their own music. They believe that music is a language understood only by a gifted few, and that it's too mysterious for those of us not born prodigies.
It isn't easy to discard a belief like that, so for now I won't ask you to. I'll simply ask you to set it aside, on a shelf in your mind somewhere, and just be willing to play and expeiment for yourself. It will get easier and easier; I promise! Ready? Click here to read the rest of this article.