OpenBuildingModels is an open, free-to-use repository for sharing and exchanging architectural 3D building models on the web. It is strongly related but not limited to the OpenStreetMap project. You can upload and link your 3D model to an OSM building and view the result in OpenStreetMap-3D ( http://osm-3d.org ), but you can also contribute or download the models for any other purpose. Try it out yourself at http://openbuildingmodels.uni-hd.de
More information can be found in the OSM-Wiki (http://wiki.openstreetmap.org/wiki/OpenBuildingModels). This project and particularly the web platform is still in early Beta stage. The project is being realized by the GIScience Research Group at the Universit of Heidelberg http://giscience.uni-hd.de .