Anyone who has lived in Japan, has seen ramune drinks - mostly likely at a local festival. There is a nice Wikipedia entry on ramune here. I did not realize that it had been invented by a foreigner, but apparently the Scot, Alexander Cameron Sim, first came up the the concoction in 1870 in Kobe.
The name comes from a Japanization of the word lemonade, and the flavor is a carbonated lemon-lime flavor. The unique bottle is also traditional and distinctive.
If any company is considering flavorings in Japan, ramune flavor should at least be considered, it is very popular with Japanese youth.
The photo is from Wikipedia under Creative Commons license.