I took this when i was in NZ back in 23 March 2008, little while ago now but hey someone might recognise the car/numberplate. Can't for the life of me remember if it was Wellington or Christchurch though.
Yep, Warrant of Fitness. Yearly compulsory roadworthy check (6 monthly for older cars).
They're good in that they keep unsafe cars off the road (instead of them catching fire on the motorways like here in QLD ) but a pain in the bum for modified cars!
It's practically a must when you're buying a car.. It'll tell you if there's any money owing on the car, whether it's been reported stolen, whether the odo has been tampered with etc. Really makes buying privately a lot easier.