Author of several best selling books (tribes, Purple Cow, The Dip and many more), Seth Godin is recognized as being one of the most influential marketing thinkers in North America. His latest book “Tribes” analyses the dynamics of tribes and will help you understand how building tribes will spread your cause/message much further than advertising ever will. While pushing you to become a leader he explains how it is easier than ever for ordinary people to create groups that will lead to significant change. He is a brilliant orator and gives several conferences a year in some of the world’s largest companies. if guy’s such as Universal and  Google listen to his advice, I think you should to. I strongly encourage you to read his blog: Seth’s blog. This will help you keep up to speed with his everyday thinking.