Tettra is a company wiki for organizing & sharing knowledge with your team
Tight is a Chrome extension that increases readability, removes many redundant/useless buttons, improves the page layout and modernizes the overall style of Slack.
It is open source (https://github.com/RileyTomasek/tight) to encourage community contribution. Suggestions and pull requests are highly encouraged!
Fastgrep is an app built for Slack that helps teams more easily find and organize links and files shared by their team members across their workspaces. All you need to do is add Fastgrep to Slack and it will start listening to all links and files that you and your teammates share. Then simply type /links or /files and voilà!