Best: lots of great sites already mentioned.
I nominate Radio NZ's makeover with all its streaming and podcast resources for the most-improved proze.

The latest, and on-going, Stinker: Ferrit.
A definitive case study of disasters: expensive, annoying and meaningless marketing (mark 1 version); nil content when you get there; fake reviews (I can't believe they still feature a Dualit toaster in the new TV ads --the same toaster featured in the 'reviews' ).
It's the latest mis-step in that long line of mostly forgotten galerias and on-line malls to nowhere.
It's main use seems to be a toilet to shovel money down. Still anything that slows and distracts Telecom can't be bad.