I’ll go first: r/kitty. One of the hundred grillion cat subs back on Reddit, the culture in this one was you posted a cat picture, and the only word allowed in the title or in any comments or replies was “Kitty.”
Someone is using that subreddit for covert communications, I just know it. Either on the level of “if u/PM_me_your_nostrils posts an orange cat, we attack at dawn!” or there’s some steganography going on with the pictures, but that subreddit was too stupid to be as active as it was.
Washing machines double as portals to another dimension which is populated by sock loving aliens who want to save the cost of manufacturing their own socks. When socks go missing in the washing machine, the aliens end up getting free and clean ones. The next time you see someone who claims to make washing machines, check if they have an otherworldly affinity for socks.