I do so dearly love living in the future.
Give this at least thirty seconds:
From Ambient Irony. As Steven Den Beste says in comments, watch her shadow.
The earworm is “Caramelldansen“, which was a popular anime video meme awhile back. I think it’s a Swedish song with a Japanese accent. The girl is Hatsune Miku, a kind of mascot for the Vocaloid voice synthesizer, which is what’s actually singing.
OK, I was a little confused. The singing in the above video is the original live recording, played at high speed for amusing effect (this is known as the “speedycake remix”). Here is a video of Miku herself singing the song, plus you get a better look at her. If you do not following computer animation technology, you need to know that Miku is animated automatically, real-time, according to a script. The above video, which incorporates her into a real scene, adds a whole ‘nother layer of computing awesomeness to the mix.
You should also see this video response to the 3-d Miku video, which is musically boring, but does involve a leek, which refers to an earlier Nordic earworm video. Again, this is happening in real-time, in response to actions in the real world.
OK, I have to go do real things now.
[one last update. I swear.]