Knowledge

Knowledge may be one of the easier things to share: It obviously doesn't get less if it is shared; it needs sharing.

General

• Free content
• Free software

• Literature
• Books

Skills/ Manufacturing

• tsolife.org - Travelling School of Life, a skill sharing network
• Instructables - website devoted to sharing knowledge on how to construct things
• wikiHow - a wiki designated to share knowledge on how to do things.