Like a wikipedia, but condensed, useful, and navigable. Preferably able to store offline / locally or decentralized. Would have to identify what basis is necessary for rebuild and what is luxury. A large majority of things today are simply luxury. I love the idea of it though and would def try and contribute somehow even though my skill and knowledge base isnt comparable to others.
An offline dump of Wikipedia would be a valuable addition to such a library. I've been thinking of storing something like this on a durable laptop stored in a Faraday cage, along with solar chargers and so on.