The 2016 IgNobel prize winners have been announced and the medicine prize went to "Christoph Helmchen, Carina Palzer, Thomas Münte, Silke Anders, and Andreas Sprenger, for discovering that if you have an itch on the left side of your body, you can relieve it by looking into a mirror and scratching the right side of your body (and vice versa)."
But I just tried this out and it did not work. I had a random itch on the right side of my face, went to a mirror, looked inside it and scratched the left side. The itch persisted until I scratched the right side.