Purple Cow Product: A product that will infect clients/buyers with so much enthusiasm that they will rave about it to their friends. Once you have a purple cow product, you incite your clients into selling it for you.
-via a magazine clipping
Marketing should begin with a differentiated product or service that gets attention (like a purple cow does among a field of brown ones). Be sure that those who care deeply about that differentiation learn about your product or service (as Krispy Kreme does by providing free donuts when it opens a new store). Those who care will e-mail and tell everyone they know (the idea virus concept). Keep adding new differentiated enhancements to your product or service (pretty soon you don't find a purple cow so interesting). Start looking for totally new business models that provide a breakthrough like your first purple cow did. Don't waste your time and money on advertising. Alternatively, it's dangerous not to do this because your product or service will be lost among all of the other brown cows (undifferentiated offerings).
-via an amazon.com comment