I think the title says it all, don't you? It should be possible to create a new contact by duplicating an existing one, either in GMail Contacts (in a full-fledged browser) or directly in the Contacts app on an Android device. This would allow, for example, adding new members of a family or new employees of a company. Then, just the new name, email or phone number (or whatever) could be entered to replace the duplicated ones and leave the remaining fields all the same. As a former Palm user, I was able to do this on that platform (primitive as it now seems by comparison to Android). Google: are you listening? How hard could it be?