I built BidsABillion.com, a provably scarce 10×10 digital ad grid where each placement becomes a permanent on-chain artifact. There are only 100 slots, and positioning is determined by a transparent bidding mechanism — higher bids secure more prominent coordinates. When a slot is claimed, the ad’s metadata (image/video reference, URL, timestamp, wallet, and bid value) is committed to the blockchain, creating an immutable record of ownership and placement history.

The system separates media hosting from settlement: heavy assets are stored off-chain, while cryptographic proofs and placement state are anchored on-chain to keep costs predictable. The backend is Python/Flask with PostgreSQL, the frontend is React, and settlement supports major chains for flexibility. The core idea is to merge digital advertising with verifiable scarcity and ownership — effectively turning ad space into a tradable, time-stamped digital asset rather than a revocable banner slot.

Feedback welcome, especially on auction mechanics and on-chain data design.