Reorder It! is an iPhone App which helps you reorder the addresses.
It's useful when contact has multiple e-mail address such as screenshots below.
I don't know why standard Standart AddressBook or other AddressBook Apps
on the store don't have this feature.
Sometimes your friend tells you "I have changed the mobile phone!" and each time he/she changes the phone, his/her address increase on your Contacts.app. Tidy it.