Firesong - Giphy for Music in Slack w/ Emoji Search
Gource - Gource is a software version control visualization tool.
Slack Meme Bot - Spice up your team conversations with memes
Octohunt - Search to find developers in your city on Github.
Yarn for Slack - Drop TV and movie clips into your Slack chats
The GitHub Matrix Screensaver - Latest commits from GitHub visualized Matrix-style