There is a worldwide push for public cultural collections to become more accessible via the internet. New Zealand has been putting its heritage collections online for a few years now but I expect there will be a big digital boom over the next five years as more museums, libraries and galleries get their collections digitised. PapersPast is perhaps the best example of an online, searchable and accessible collection but others are on the way.
I find the Transactions and Proceedings of the Royal Society of New Zealand fascinating reading. This is a searchable and accessible database of articles written by the very first botanists and biologists to explore New Zealand. Again, this is a National Library project like PapersPast.
The National Register of Archives and Manuscripts (NRAM) is a voluntary register for libraries, museums and anyone with something archivable. Archives include minute books, letters, diaries, and other personal or organisational papers. Basically anything that was written down and not formally published is an archive and could be catalogued there. It is searchable but not accessible - meaning you can't click on a link and read the actual document.
Archway is a database that lists government-generated archives from various departments. There is some early settler information to be found such as land sales and wills - anything that involved interaction with a govt department. But you have to visit the archives building in Dunedin to actually see them. In some cases you may have to get written permission from a department before you can access them.
NZ Museums (a National Services Te Paerangi project) is undergoing a massive makeover to allow museums to put photos and information on their website. Each museum will be able to feature photos of special objects and images in their collection. They aim to have the new website launched by August 2008. This will be a boon for smaller museums (such as the Otautau Museum) to make their collections searchable and viewable.
Te Papa has a very good searchable database of some of its taonga and collections. The Hocken Library has searchable databases but not accessible. Unfortunately the Southland Museum and Art Gallery has no search facility at all on its website. Hopefully they are in the process of putting their collection online.
Although it's not a collection per se, I also really like the Dictionary of New Zealand Biography. And there's a privately owned company with online databases called The Knowledge Basket. They feature taonga such as Elsdon Best's books on Maori culture which are completely searchable and accessible, word for word.
There are lots of opportunities to explore New Zealand's artefacts, culture, and history online. With the digital revolution powering ahead, access to these wonderful resources can only get better. If you know of other websites, please leave a comment!