A friend in an IRC channel (thanks topz) posted a link to this awesome video of Nagi-sama singing the Kannagi opening song, Motto Hade ni ne!, and I just had to share it ^^.
Apparently, the video was made by a new software application called Dance Mixer that allows you to create a character, customize her appearance, and then program her to dance to your imported songs ^^. There doesn’t appear to be a demo of the program available and it costs 15,980¥ so I haven’t had a chance to try it myself >_<
More videos at their Youtube channel: http://www.youtube.com/dancexmixer