Came across an interesting idea for the answers to those ubiquitous secret Q & A they use for authentication.
If you see someone lives in NZ and the question is:
Where where you born?
a hacker could answer "Auckland" / Wellington" / "Christchurch" / "Dunedin" and that would cover about 80% of the possibilities since e.g. over 25% of the people in NZ live in Auckland.
So the suggestion is to use a random phrase to answer everything.
"Where were you born"? = Puddleduck
"Mother's maiden name"? = Puddleduck
and so on.