RightGIF - Less noise, better GIFs. A better /giphy for Slack.
Now UI Kit - A beautiful Bootstrap 4 UI kit. Yours free.
Slack Meme Bot - Spice up your team conversations with memes
Bots UI Kit - Fully customizable Sketch UI Kit for Messenger Platform
Yarn for Slack - Drop TV and movie clips into your Slack chats
Landing UI Kit - Handcrafted UI components for landing pages