So far, only exercises for my pupils, a rather predictable guitar piece and a string orchestra doodle have come out of all that playing with it, but who knows and it's fun (and I even learn and re-learn things along the way). Interesting times, though, when you can be writing a sonata (or a song) in the Tube -and listen to the results straight away. I imagine my music teachers would wince at that. You weren't allowed a piano in the room in composition exams, you had to be able to hear it all in your head. Which makes sense, but it still is so much better to actually hear it.
I expect only one person in my flist will get the quote in the subject title... :P