The blades are developed by engineers from Künzelsau (Germany).
Joachim Dietle: "The owl is the bird with the least wing noise" (this is true, mice can't even hear them approaching).
I have no idea how they incorporated the shape or other parameters into a fan blade.
The fan blade does have toothed sides.
![Image](http://www.hartware.de/media/news/41000/41665_1b.jpg)
Claimed results of the 80 cm (!) fan: 10% higher efficiency, and half as loud as the competition.
The fan was built with climate control and cooling technique (general) in mind, but could ofcourse be reduced in size to fit a PC.
I'm very sceptic but it sounds interesting.