Here are a few screenshots showing different parts of FreeCAD. See more screenshots submitted by FreeCAD users in the screenshot forum thread and in the "Show your project here!" Users Showcase forum part.
A jeep modeled by psicofil
A house made with the Arch Workbench by rockn
Mesh curvature analysis by the Mesh Workbench
Export to external applications with python macros
Assembly of multiple objects
A fully-constrained sketch revolved to create a bike rim section