VariCAD is a 3D/2D CAD system for mechanical engineering. In addition to standard tools for 3D modeling and 2D drafting, the CAD system provides tools for sheet metal unbending and crash tests, libraries of standard mechanical parts (ANSI, DIN) and symbols, mechanical part calculations, and tools for working with bills of materials (BOMs) and title blocks. VariCAD supports STEP, STL, IGES, DWG, and DXF file formats.
GNUSTEP Live CD contains a lot of software for GNUstep, a free implementation of the OPENSTEP framework (which is also directly used in Mac OS X as Cocoa). It includes excellent applications for RAD (GORM and ProjectCenter). The CD is available for i486, AMD64, Apple Mac PowerPC, and Sun UltraSPARC computers.