Hatsune Miku
A series of rhythm games starting from "" were produced by Sega under license using Hatsune Miku and other Crypton Vocaloids, as well as "fan-made" Vocaloids like Akita Neru. TinierMe also made attire that looks like Miku's for their services, allowing users to make their avatar resemble her. The series has sold 6million copies. "" was developed for the Nintendo 3DS. Miku's appearance in this game is based on the Nendoroid series of figures. Hatsune Miku is also briefly referenced in the game "Recettear", where a young man stargazing sees "The Green-Onion Girl" constellation. Also, in 2013, Saki Fujita voices Fei-Yen HD, a character based on one of Hatsune Miku's modules, in "Super Robot Wars UX"; this appearance does not use Miku's vocal library.
Vocaloid
The software became very popular in Japan upon the release of Crypton Future Media's Hatsune Miku Vocaloid 2 software and her success has led to the popularity of the Vocaloid software in general. Japanese video sharing website Niconico played a fundamental role in the recognition and popularity of the software. A user of Hatsune Miku and an illustrator released a much-viewed video, in which "Hachune Miku", a super deformed Miku, held a Welsh onion ("Negi" in Japanese), which resembles a leek, and sang the Finnish song "Ievan Polkka" like the flash animation "Loituma Girl", on Nico Nico Douga. According to Crypton, they knew that users of Nico Nico Douga had started posting videos with songs created by the software before Hatsune Miku, but the video presented multifarious possibilities of applying the software in multimedia content creation—notably the "dōjin" culture. As the recognition and popularity of the software grew, Nico Nico Douga became a place for collaborative content creation. Popular original songs written by a user would generate illustrations, animation in 2D and 3D, and remixes by other users. Other creators would show their unfinished work and ask for ideas. The software has also been used to tell stories using song and verse and the "Story of Evil" series has become so popular that a manga, six books, and two theatre works were produced by the series creator. Another theater production based on "Cantarella", a song sung by Kaito and produced by Kurousa-P, was also set to hit the stage and will run Shibuya's Space Zero theater in Tokyo from August 3 to August 7, 2011. The website has become so influential that studios often post demos on Nico Nico Douga, as well as other websites such as YouTube, as part of the promotional effort of their Vocaloid products. The important role Nico Nico Douga has played in promoting the Vocaloids also sparked interest in the software and Kentaro Miura, the artist of Gakupo's mascot design, had offered his services for free because of his love for the website.