BIM (Building Information Modeling) is a paradigm for 3D CAD models made for Architecture, Engineering and Construction (AEC). Long a closed, proprietary garden, it becomes more and more an open, hackable world thanks to several Free and Open-Source tools and formats. This talk will try to illustrate how rich that world has become when your tinkering, hacking, coding itch starts to scratch... In this talk, Dion (developer of BlenderBIM) and Yorik (developer of FreeCAD, specifically its BIM tools) will use these two applications and try to show some clever tricks that you can do with BIM models, that no proprietary software would dream to achieve.