This free collection library comes from IT University of Copenhagen.
http://www.itu.dk/research/c5/
There is a video with one of the authors on Channel 9. I am t
In addition to that omer van kloeten's points.
The open source licence is MIT (comparable to BSD licence) this means that if you need make changes to the library you don't have to open-source the changes. (this might be a problem with some companies). For GPL-type licences this can be a problem.