Simon Willison’s Weblog

zipdecode (Java Applet). Type a zip code (try 66044) and watch the USA get narrowed down. Brilliant.

Posted 17th September 2004 at 9:37 pm

Recent articles

Video: Building a tool to copy-paste share terminal sessions using Claude Code for web - 23rd October 2025
Dane Stuckey (OpenAI CISO) on prompt injection risks for ChatGPT Atlas - 22nd October 2025
Living dangerously with Claude - 22nd October 2025

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