OneBar - AI-powered Q&A knowledge base for Slack teams
Slack News Feed - Get the top posts from every Slack chat you're in.
Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
Slinky - Your slack links — organized!
Linen - Business Tools, Collaboration, and Slack Tools
Lurchr - Saves all your Slack links, so you can focus on work