I work in a team closely related to another team, and together we're about 30 people in the midst of THOUSANDS of engineers responsible for shipping product. We are dying under the burden of tracking and correlating engineering decisions across product lines and customers through presentations (you can't have a meeting without PowerPoint!) and spreadsheets -- scattered all over internal shared drives -- email, and Skype chats (which the company won't allow history for). Just this week, I'm supposed to start working on a plan to implement a knowledgebase system to capture all of this information. Obviously, I'm very interested in the answers here.

The original question was about sharing knowledge amongst a TEAM, but almost all of the responses are about PERSONAL systems. I know most people watching this board are small-company startup types (in general), but I'm hoping that some of the old codgers, like me, working in creaky, legacy firms, have more to say. If we can't find something off-the-shelf here, I'm going to wind up writing some kludgy homegrown tool with Elasticsearch, and, frankly, this just doesn't interest me. I need answers people! The leader for large teams, according to what I see here, seems to be Confluence. Notion LOOKS cool, but putting this data in someone else's hosted service is an absolute non-starter for us.