tracking of bank notes is already in action, its called "Cycle-Cash Visibility and Collaboration" (german article) https://netzpolitik.org/2025/bargeld-tracking-du-hast-ueberwachungsinstrumente-im-portemonnaie/#netzpolitik-pw

There is a community added experimental feature to switch from Core to Knots coming with next RaspiBlitz v1.12.0 release.

Pneumatic Tube Transport (Rohrpost) https://youtu.be/m3_cH1iYoUo

spain summerhit 2018 :)

https://youtu.be/17_MKvJ4u24

https://youtu.be/lIlMnEdJB-E

That escalated quickly :) #Bitaxe

New RaspiBlitz Tutorial: How to accept Lightning donations with LNBits and Cloudflare tunnels https://bennet.org/blog/accept-lightning-donations-with-lnbits-cloudflare-tunnels/