Buy an ad in $PAPER. Anyone can take it for 1.5× what you paid, and you get 1.3× back. Ads nobody takes get cheaper every week.
Buy. Pick an empty inch, write up to 90 characters and an optional link. Pay the price in $PAPER. The first sale of every inch is burned.
Take. Any printed ad can be taken for 1.5× its last price. The old owner is paid 1.3× automatically, the rest is burned.
Fade. An ad nobody takes loses 10% of its take price every week, never below the base price.
Edit. Owners can change their own ad any time by signing with their wallet. Free.
Payments go to the paper's wallet; a bot pays out owners and burns every 30 minutes. Every payout is a transaction. Nothing here promises profit: you get paid only if someone outbids you.