Lurchr - Saves all your Slack links, so you can focus on work
Slack It - A bookmarklet to share links in Slack with one click
Google Drive to Slack - Slack notifications whenever you work on Google Drive docs
Heymarket for Slack - Text and Facebook messaging from Slack
Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
MovetoSlack - Migrate from MS Teams to Slack in 5 minutes