So, a ways back I posted a link to a site with this animation:http://www.nyaatorrents.org/images/HatsuneMiku.swf
(in case that doesn't want to embed, try the link directly to the SWF
I saw a couple girls cosplay as her months ago at AnimeExpo, but I had no idea what she was from. Eventually I got curious.
As you can see from the URL, her name is Hatsune Miku. Now just enter that into Wikipedia and...
Vocaloid is a singing synthesizer application software developed by the Yamaha Corporation that enables users to synthesize singing by typing in lyrics and melody.
Hatsune Miku (初音ミク?) is the first installment in the Vocaloid 2 Character Vocal Series released on August 31, 2007. The name of the title and the character of the software was chosen by combining Hatsu (初, First?), Ne (音, Sound?), and Miku (未来, Future?). The data for the voice was created by actually sampling the voice of Saki Fujita, a Japanese voice actress. Unlike general purpose speech synthesizers, the software is tuned to create J-pop songs commonly heard in anime, but it is possible to create songs from other genres.
The character's first appearance in an anime is in (Zoku) Sayonara Zetsubō Sensei, where she (and various other people and characters) try out to be the voice of Meru Otonashi. For online multi-player games, the Japanese version of PangYa started a campaign with Hatsune Miku on May 22, 2008 in which a player could purchase her outfit for one of the characters.. Her first appearance in a video game is in 13-sai no Hello Work DS (13歳のハローワークDS?) for the Nintendo DS where she is included as one of the characters. Hatsune Miku was given a PlayStation Portable game called Hatsune Miku: Project DIVA that was released on July 2, 2009 by Sega. Hatsune Miku made a cameo appearance in the Lucky Star OVA in the form of Kagami's cosplay in her dream. She made a vocal appearance in the finale ending theme of the anime Akikan!. Hatsune Miku received the 2008 Seiun Award in the free category. She is also a playable character in the game Tales of Graces as downloadable content for 400 Wii points.
That is... I don't even know the word to use.
Completely unrelated random fact: tonight I went to a social event with the people form Obsidian Entertainment, and encountered... a girl with kitty ears. Apparently she always wears them, as her (abbreviated) name is Kitty. I have no idea if there's any connection to anime.