Something that I miss very much is library for multidimensional/spatial data structures.
I strongly agree with this too. I often develop libraries that are related to 3D geometry, and I always end up regretting that there doesn't exist any somehow "standard" spatial data structure that wouldn't be related to any particular implementation or product. As a consequence it's very difficult in this domain to deliver libraries that are really portable and easily integrable. As we're talking about geometry, I have an idea to propose, that came to my mind a couple of times. It would be to have a Boost library that portably handles 3D hardware acceleration capabilities by wrapping the most widely used implementations (I obviously think about OpenGL and Direct3D). I already saw some discussions about this need on the Boost mailing lists and it's a strong need for me too. The two main interests would be : abstracting the different implementations, and bringing the powerfulness of C++ to those C APIs. Unfortunately this proposal breaks one of the requirements of Boost: no dependency upon any external library. A wrapper obviously depends on what it wraps... so I guess this idea has little chance to be accepted. Bruno