It was on HN last year:
http://news.ycombinator.com/item?id=2431318
This is the related code: https://github.com/albertz/shairport/
This is the related code: https://github.com/albertz/shairport/
snos has the correct link above, from the beginning of the video, it looks like he's running airplay-nmt: http://code.google.com/p/airplay-nmt/