It's easy - just select the desired access level, copy this link and send it via email, instant message, etc.Link: Just a link to your wiki. Post this anywhere and people can ask you for the invite key.
Jim Benson mocked up a java-based concept map spinning off from this popular book, the "Wisdom of Crowds"
Check out The Big Picture at CNET News.com. Editors link up stories with other relevant stories, companies and topics in a clickable, dynamic concept map.
Eileen Clegg offers another web-based concept map called, she calls a Visual Story. This hand-drawn map was developed for 6th grade science students in California.