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@@ -243,6 +243,8 @@ x402-enabled APIs and production services. No API keys. No accounts. Pay USDC pe
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 - [HydraTrader x402 Catalog](https://x402.hydratrader.ai/.well-known/x402) — Three pay-per-call Base USDC helpers via x402 (no API key): `POST /v1/cheap-errand` ($0.01) summarize/rewrite/classify/keywords/sentiment/translate; `POST /v1/structured-extract` ($0.03) schema-bound extract from pasted text or public URLs; `POST /v1/research-brief` ($0.08) short public-web briefs with citations (fair-use snippets only). ([SKILL](https://x402.hydratrader.ai/SKILL.md) | [OpenAPI](https://x402.hydratrader.ai/openapi.json) | [llms.txt](https://x402.hydratrader.ai/llms.txt))
 
+- [Penny Press](https://www.pennypress.org/.well-known/x402) — Original essays on freedom, economics and philosophy; free for humans, pay-per-read for machines via x402 micropayments in USDC on Base mainnet.
+
 ## Production Deployments (High Volume)
 
 - [AIsa](https://aisa.network) — Leading x402 payment processor. **10.5M+ cumulative transactions** on the x402 network. The benchmark for production scale.