Problems: Decentralisation with P2P software.
Distributed history search
Rather than indexing the entire internet, index everybody's browsing history to find content
Would you share your browser history to help fellow internet users? A user would then use a special distributed search that searches peers first and then a real internet search second. This would be a form of contributing to your peers for useful content. Such as searches for products and documentation.
// Would you share your browser history to help fellow internet users? //
Conditionally - yes, and more, there are ideas floating around of sharing DOM, parsers, etc., which are ways to taking back the Internet.