Memonia - Automatic knowledge discovery and sharing for Slack
Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
Slack-News - Read news from multiple sources within Slack by just typing
OneBar - AI-powered Q&A knowledge base for Slack teams
Slack It - A bookmarklet to share links in Slack with one click
PigeonBot - Send emails via Slack with the /email command