Eng-Tips

Mechanical Engineers technical support forums and mutual help system for engineering professionals. Selling and recruiting forbidden.
http://www.eng-tips.com/gthreadminder.cfm/lev2/16/lev3/58/pid/404

ICrank

Mechanical Engineering portal site. Includes vendor and newsgroup directories, reference data, a product development forum, technical information and links to mechanical engineering resources.
http://www.icrank.com

MechanicalEngineer

Job listings for mechanical engineers and related jobs. Also a forum for open discussions, and a list of recommended books on the field.
http://www.mechanicalengineer.com/

Mechanical Design Resources

Links to Engineering Associations, Materials, Components, Design Information, Patents, Publications, Engineering Sites, Safety and Finite Element.
http://www.gearhob.com