When dealing with CAD models, you often have the problem converting your model into a .stl file OpenFoam meshers need. Here are some examples that might help you there:
SALOME (http://www.salome-platform.org/)
CFmesh (Meshing Software & CFD - Creative Fields)
ENGRID (http://engits.eu/en/engrid)
GMSH (Gmsh: a three-dimensional finite element mesh generator with built-in pre- and post-processing facilities)
Triangle (Triangle: A Two-Dimensional Quality Mesh Generator and Delaunay Triangulator)
Tetgen (http://tetgen.berlios.de/)
Overture (http://www.overtureframework.org/)
Google SketchUp (http://sketchup.google.com/)
Free-CAD (FreeCAD download | SourceForge.net)
Blender (http://www.blender.org/)
MeshLab (This domain was successfully registered for the highest bidder in our weekly auction.)
ParaView (http://www.paraview.org/)
Gnuplot (http://www.gnuplot.info/)
OnShape (http://www.onshape.com/)
Inspiration: OpenFoam group on LinkedIn (OpenFoam)
Feel free to add more in the comment section!