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When Eric Wilhelm finished his PhD in mechanical engineering at MIT, he and three friends started Squid Labs, a consultancy based in Emeryville, CA, that finds fixes for clients' technical problems (how to make solar-collecting concrete, for example). But Squid Labs was also founded as a place where the colleagues could explore their own projects and ideas--funding them through their consulting jobs. In 2005, Wilhelm had an idea for a how-to website where people could share step-by-step visual instructions for original projects. The team spun the site out into its own company, and Instructables was born.

Wilhelm had hit upon the idea at the right time, just as the spirit behind open-source software began permeating other technological fields. Instructables offers its growing community of more than 300,000 registered users an easy way to document do-it-yourself technology projects and share ideas with others. --Kate Greene