SolidWorks  
   A solid modeling program for mechanical engineers and designers, as well as add-on applications.
   http://www.solidworks.com/

MCS, Inc.  
   Makers of the Anvil Express software for mechanical design, that also has manufacturing features.
   http://www.mcsaz.com/

CoCreate  
   A software subsidiary of HP that develops mechanical CAD and design management software.
   http://www.cocreate.com/

IronCAD  
   Solid modeling software for mechanical designers and engineers.
   http://www.ironcad.com/

MechSoft  
   Database of standard parts with tools for performing mechanical calculations, for use with many CAD systems.
   http://www.mechsoft.com/

VariCAD  
   2D/3D mechanical engineering CAD System for Windows and Linux.
   http://www.varicad.com/

Ashlar Inc.  
   Vellum 3D CAD program and Vellum Solids 3D modeling software.
   http://www.ashlar.com/

SteelCad  
   Steel detailing software with packages for structural design, detailing, and manufacturing.
   http://www.steelcad.com/

Function Bay, Inc.  
   Virtual prototyping of complex mechanical systems with the RecurDyn software products.
   http://www.functionbay.com/

Engineering Software Solutions  
   Developers of engineering based design software for special requirements in industries such as petrochemical, ship building, mining, civil, mechanical, structual, manufacturing, defence and aerospace.
   http://www.ess.com.au/

Think3  
   Produces mechanical CAD software for conceptual design through engineering to manufacturing for products in many industries.
   http://www.think3.com/

Drew's MCAD Connection  
   A technical resource for users of Autodesk's MCAD products including Mechanical Desktop and Inventor.
   http://www.mymcad.com/

freeCAD  
   A basic CAD program for creating collections of 3D elements, which can be connected by joints, constraints, actuators, springs, dampers, or forces for running motion simulations.
   http://www.askoh.com/

ProSpur+  
   A program designed to create drawings of spur gears, as symbols for ProCAD+ on Acorn RISC computers.
   http://www.dsnell.zynet.co.uk/PS/ProSpur.html

Pilot3D  
   A relational trimmed NURB curve and surface 3D modeling program, useful for boat hulls and other applications.
   http://www.pilot3d.com/

Solid ConceptMecaSoft  
   Develops and sells SolidConcept, a parametric 3D solid modeling software for creating parts, assemblies and automatic 2D drawings.
   http://www.solid-concept.com/

Sigmetrix LLC  
   Develops and supports CE/TOL, a tolerance and variation analysis software package for mechanical design and manufacturing processes.
   http://www.sigmetrix.com/

SnapCAD  
   A mechanical design software package for TEMA type shell and tube heat axchangers and ASME pressure vessels.
   http://www.snapcad.com/

Intergraph SmartSketch  
   A 2D parametric drawing program for Windows, that works on AutoCAD and MicroStation files.
   http://www.intergraph.com/imagine/

CADables  
   TurboCAD hatch patterns, color palettes, and related resources.
   http://catalog.stormloader.com/

Saga Software  
   TabletCAD is a computer program for designing medicinal tablet shapes, calculating tablet volume and surface area and producing tablet technical drawings.
   http://simnet.is/sagasoftware/

Autopipe  
   Software that calculates piping code stresses, loads, and deflections under static and dynamic loading conditions, with special features for buried pipeline analysis, wave loading, and fluid transients.
   http://www.autopipe.com/

Sheet Lightning  
   Specialized engineering 2D/3D CAD shareware for sheet metal design and unfolding for fabrication and manufacture. It handles cylinders, cones, square-to-round adapters, ovals, intersections and multi-intersections.
   http://www.revcad.com/SheetLightning/default.htm

Zetaline Projects Limited  
   Presents the PipeData-Pro software family for piping designers and engineers [requires JavaScript and Flash].
   http://www.pipedata.com/

Romax Technology  
   Develops software for gear box design, dynamic simulation of gear shift synchronization, and related tasks.
   http://www.romaxtech.com/

Autodesk Inventor  
   Solid modeling package for 3D mechanical design.
   http://www.autodesk.com/inventor

Autodesk Inventor Tutorials by Sean Dotson  
   Basic and advanced tutorials on the use of Autodesks Inventor software, with file library, design gallery and discussion forum.
   http://www.sdotson.com/

SketchCalc  
   A software that allows to calculate the properties of arbitrary profile sections, imported from DXF.
   http://www.sketchcalc.com/

Steelcad Consultants A/S  
   SeaSolution is a tool for geometric simulation and design focused at ship building and shell plates development.
   http://www.seasolution.com/

Revware, inc.  
   Feature-based reverse engineering software for SolidWorks.
   http://www.revworks.com/