OneBar - AI-powered Q&A knowledge base for Slack teams
Slack News Feed - Get the top posts from every Slack chat you're in.
Whatis - Manage & organize your team's knowledge straight from Slack
Slinky - Your slack links — organized!
Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
PigeonBot - Send emails via Slack with the /email command