Gource - Gource is a software version control visualization tool.
VixT on Slack - The best video mashup app now on Slack.
Codeology - Open-source algorithm that visualizes GitHub projects
Slack Meme Bot - Spice up your team conversations with memes
The GitHub Matrix Screensaver - Latest commits from GitHub visualized Matrix-style
GoGifApp - Free Slack GIFs App, multiple images to pick from at once