Thanks for the quick reply.
What i mean to say is, suppose a customer saves 3 separate billing addresses and 3 separate shipping addresses. When he logs into his account, how can he view all the 6 addresses that are saved by him.
My second question is, it would be good if the customer is to able to see all the 6 addresses in the check out page and can just click to select any one of the addresses to set the shipping and billing address for the current order. I have seen this feature in a few website. Is it possible.