Hey folks, there's a new version of DAZ 3D Studio and it's free: http://www.daz3d.com/
It includes some free models.
A lot of free models. Every week DAZ 3D site releases a new model for free to users subscribed. Furthermore, in the starter pack there is Aiko3 a full female model, with different clothes available. I also discovered that, inside the base installation, there are 3 LODs of Victoria 4, in OBJ format, that can be imported easily inside Blender.
All DAZ models are OBJ format, plus some Poser files for skeletons and poses and, eventually, special DAZ 3D files for other data. OBJ and Poser files are both plain text and Blender has importers and exporters for them. DAZ 3D formats are XML.
DAZ 3D exports also Collada. And has a scripting environment (based on ECMA script: i.e. JavaScript) that permits to develop further exporters and tools.