Flixier - Flixier Pro is an online video editor that speeds up your workflow with 1 minute rendering on any device, streamlined communication and collaboration features and plenty of cloud storage.
RightGIF - Less noise, better GIFs. A better /giphy for Slack.
Spark Camera - Make memorable videos
Slack Meme Bot - Spice up your team conversations with memes
Showbox - Showbox helps you to create studio quality video in minutes.
Yarn for Slack - Drop TV and movie clips into your Slack chats