This isn't a thread for discussing armed revolutions or radical social engineering projects, but for minor things that could realistically be changed to improve our day-to-day lives in some way.
My first idea is that it would be nice if I could do an internet search that was restricted to only websites that I've bookmarked, or that are in my browser's history, or filtered in some other way based on my past activity. Sometimes I'll think of something I saw online weeks, months or even years ago, like an interesting article or a product that was for sale, but I won't remember what site I saw it on and can't find it again with Google, often because there are too many other sites flooding the search results with things that are similar, but not quite what I'm looking for. I'd like to be able to do this without revealing information about my past browser activity to Google or other search providers in a personally identifiable form, so it should have a secure annonymising system that separates the information from the source's IP address, and also splits the information up so that assticklers.com isn't sent in a big chunk of data along with frank56.adultblogservice.com and foocorp.com/boardofdirectors/frankharvey.