alt Hacker NewsYou could put your onion address into an “oh by code”[1] and just write it down … or chalk it on the sidewalk for someone to see … post it on a physical bulletin board.. hold it up on a sign…
This way you could establish communication with an unknown future party, totally offline.
[1] https://0x.co
Trying to repurpose hex literal notation as a "recognizable" URL shortener seems like a questionable idea. At least write it as 0x.co/FFFF so it's obvious to readers how to interpret it.
If you're printing something why not go with a QR code?