Market size: Medium (< 10,000,000 people)
Investments required: Medium (< US$5,000,000)
I often see when a pianist plays another person is sitting by and doing nothing but turning music notes pages. What a waste of human resources!
Today, we have e-book readers. The same technology can be used to producing music notes readers with a remote control for turning pages. A pianist could turn pages with a slight move of his neck, of other part of his body.