Software used by the two courses.
The CAD software we use for the Parametric Design Class at Stanford, Digital Project, is a variant of the enterprise CAD solution developed by Dassault Systémes; CATIA. DP has been developed over a number of years by Gehry Technologies to address the need of Architectural projects.
If you haven't found this already, the GT Wiki acts as a collaborative help and community.
The main CAD app used at Luleå University of Technology will be Siemens NX. The software was originally developed by McDonnell Douglas' Unigraphics Group and is in functionality and scope on par with Catia and Pro/E.
Enterprise Architect by Sparx Systems is a good tool for building models using UML. Add the MDG SysML plug-in to work with SysML.
yEd is a free and easy to use graph modeler that can be used for sketching out diagrams. The advantage over other drawing/diagramming tools is the wide collection of built in automatic layout tools.