Principles of influence

I recently read Influence: Science and Practice by Robert Cialdini, which was fascinating.  I just want to keep a list here of the influence tactics he describes:

• Perceptual contrast (starting high)
• Reciprocation (uninvited debts, unequal exchanges)
• Maintaining consistency (due to public commitment)
• Social proof (going along with the crowd)
• Likability (attractiveness, similarity, compliments, familiarity, and cooperation)
• Authority (or seeming authority)
• Scarcity (of quantity or time - making it a competitive situation)

Really important stuff to know, both as a marketer and an everyday citizen.