http://www.salome-platform.org/

Never heard of this one until yesterday. GPL and looks very very heavy duty. And it works well on my anemic atom Ubuntuized computer.

I think it's worth checking out.

Or, as the Salomeians say on their site "


Supports interoperability between CAD modeling and computation software (CAD-CAE link).
Makes easier the integration of new components into heterogeneous systems for numerical computation.
Sets the priority to multi-physics coupling between computation software.
Provides a generic user-friendly and efficient user interface, which helps to reduce the costs and delays of carrying out the studies.
Reduces training time to the specific time for learning the software solution based on this platform
Provides access to all functionalities via the integrated Python console.
"