The entire internet (world-wide-web) can be thought of as a rudimentary knowledgebase. The resources on the web and the search engines that allow us to find these resources are the baby steps towards the goal of a world-wide-knowledgebase.
I sometimes think of blogs as a tiny knowledgebases but the reality is that blogs fall far short. Blogs represent only a tiny fraction of the authors’ knowledge. For example, in this blog, I deliberately avoid writing about quantitative finance and computer programming. In physics, I only touched on few important questions. In spiritual philosophy, I only provided a summary of my synthesis. This is also true for all other blogs. This is true with the entire internet content as well. Knowledge represented by the entire internet is only a tiny fraction of the knowledge accumulated by humanity. The information capacity of the internet is growing at an incredible rate but internet as a knowledgebase is still in its infancy.
Repositories of knowledge
Scientific journals that publish refereed papers maintain their archives on the internet these days but unfortunately most of these archives are behind pay walls. They are not freely accessible. But, there is also a movement towards open access. In physics Europeans are leading the way. Please see my blogpost about refereed open-access journals in physics.
Newspaper archives are available on the internet. That’s very important.
Please see the list of other online encyclopedias here.
I will mention Wolfram Alpha here. Wolfram Alpha is not free but it is an important step towards the goal of world-wide-knowledgebase.
Best answer sites
There is a lot of information in the Google Trends but it takes a lot of effort to extract information.
Importance of the “Search” box
Please consider adding the “Search” box to your blog sites. The “Search” functionality is the most important component towards the world-wide-knowledgebase.
What we have so far is wonderful but this is just the beginning
What we have so far is information curated by human beings. In the next step, information of the world will be curated by machines. That phase will be followed by another phase where human beings will organize the machine-curated information into an early form of world-wide-knowledgebase. Then there will be another phase dominated by machine processing. These human-touch and machine-touch dominated phases will follow each other.