Simon Willison’s Weblog

Largest Living Thing Is a 2,200 Acre Fungus in Oregon. 2,000 years old and mostly harmless.

Posted 18th February 2004 at 9:24 pm

Recent articles

GPT-5: Key characteristics, pricing and model card - 7th August 2025
OpenAI's new open weight (Apache 2) models are really good - 5th August 2025
ChatGPT agent's user-agent - 4th August 2025

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