InnoCentiveAn online marketplace of ideas and solutions. Visitors are either a "seeker" (a company or entity in search of a solution to a challenge) or a solver (a company, entity or person that offers a solution to a challenge submitted by a seeker). Seekers pay solvers for solutions that work for them. Challenges are listed in 4 categories by matter of complexity—one challenge resembles an online brainstorming session, others require greater levels of detail, sophistication and specificity to "solve."
InnoCentive was started in 2001 by Eli Lilly and began its life serving the chemistry and science worlds. The site has since grown heavily into engineering and design and business and entrepreneurship. Whether you seek or solve (or neither), InnoCentive is a great site to witness the power of manufacturing.