Getting HRTF from 3-D scan + acoustic simulation
There are various school of thoughts about this. A German guy named Klaus Genuit came up with a parametric model of HRTFs that's based on the actual physcial geometry of head, shoulder, pinna, etc. He actually now runs a company that craeates binaural products and measurement gear, see for example
http://www.head-acoustics.de/downloads/publications/binaural_technology/DAGA_99_Physical_Modeling_of_individual_HRTFs.pdf

Based on this work you could potentially create individual HRTFs using a some 3D scanning scheme. I do vaguely remember a company coming doing exactly that for a bunch of people at my employer at the time. I didn't think the HRTFs that came out that way were particularly good but I didn't do a lot of work with them either.

Individualized HRTFs only help to a certain extent. Let's say you want to record a concert. You can do this binaurally using a dummy head. However, there is currently no way to convert this recording to your individual HRTFs after the fact, even if you have them.