Customer Service Interview Questions

Can you tell me about a time when you did some thing extra, which was not part of the routine activities assigned to you, but you did it for the benefit of the customer?
How do you handle negative feedback from very angry clients? How do you respond to him/her?
Explain with an example, how would you handle a situation where a customer is asking for something, which is not in the interest of the company or which would violate a policy of the company?
You ever felt, during course of your work, that the existing systems and solutions are not sufficient to meet the needs of customers properly and/or that they need to be changed? If so, tell me more.
Can you explain how you contact or initiate communications with customers?
If you had to turn down a request from a valued client, what would you do?