Paul Graham is many things — a writer, computer programmer and language designer, a painter, a venture capitalist. Among other contributions, he suggested the mathematical model used by most email systems to filter spam.
Etherpad is a collaborative, web-based text editing tool. It can also reproduce every change you’ve made to a document. Think of it as infinite undo, an animation that reveals the process of editing, played back frame by frame.
Combining the two:
Watch Paul Graham write a summary of his 13 tips for startup companies — from keystroke #1 to #5465.
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