Usetiful - Fight user churn with great user onboarding. Interactive product tours and smart tips significantly improve your user retention.
Stonly - Create interactive step-by-step guides
User Onboarding - Onboarding teardowns of popular sites/services
Checklisty - Increase trial conversion.
UserGuiding - User onboarding made easy, for less. Create product walkthroughs in a couple of clicks, without breaking the bank.
Marketing Examples - A gallery of real world marketing case studies. Updated every day.