UI Movement - The best UI design inspiration, daily
PlayPlay.io - Chess and Ping Pong tracking in Slack
Design Hunt - Curated design inspiration for everyone
Pinpon - The ping pong bot for Slack
UI Jar - Hand-picked design inspiration for your real life projects
Ranked.Fun - An online leaderboard with your friends for your favorite games (Ping Pong, Foosball, Smash Ultimate, Chess, etc.)