This large sound art festival is on right now, just over the border in Belgium. Well worth the trip

Invisibilité acoustique

Kind of "invisibility cloak". The acoustic cloak developed by these researchers contains 120 aluminium cylinders 15 mm in diameter, surrounding a 22.5 cm cylinder. The position of each cylinder in the cloak has been obtained by using optimization techniques based on genetic algorithms (numerical algorithms which mimic Darwinian evolution).
http://www.uv.es/uvweb/college/en/news-release/first-experimental-tridimensional-device-acoustic-invisibility-has-been-designed-1285846070123/Noticia.html?id=1285875404982

A3 FutureAcoustic

Technologie qui analyse le bruit ambiant pour créer un son musical qu'il superpose au bruit afin d'en atténuer l'effet désagréable.

http://www.actinnovation.com/innovation-technologie/futureacoustic-la-technologie-a3-transforme-en-temps-reel-le-bruit-ambiant-en-musique-2241.html
http://www.futureacoustic.com/page.php?section=1&no=35
http://kpacoustics.com/