In the 19th century, piano makers competed to make special instruments for Hungarian virtuoso Franz Liszt, the world’s first piano superstar. Now Hungary is returning the favour with a space-age piano named for its creator, pianist Gergely Boganyi. “The Boganyi,” unveiled on Tuesday, has two legs, uses carbon composite as well as wood and employs wild curves to get a more powerful and balanced sound than that of similar-sized conventional models.