In 1991, computer scientists Quentin Stafford-Fraser and Paul Jardetzky at the University of Cambridge computer laboratory were tired of walking to the Trojan Room only to find the coffee pot empty. They aimed a 128 by 128 pixel grayscale camera at it, wired it to a video capture card in an Acorn Archimedes, and split the software: Jardetzky wrote the server that grabbed frames, and Stafford-Fraser wrote XCoffee, a client for the X Window System that showed a tiny image refreshing every few seconds on researchers’ screens across the lab’s local network.

In 1993 the Mosaic browser brought inline images to the web, and in November of that year Daniel Gordon and Martin Johnson connected the feed over HTTP so anyone could reload a page and see the pot. It became the world’s first webcam and drew visitors worldwide for nearly a decade. When the lab moved to the William Gates Building, the feed was cut on August 22, 2001, at 09:54 UTC, with a final frame showing a hand reaching in to switch it off. The last Krups machine then sold on eBay to Der Spiegel for £3,350.

• Over its life the camera watched four or five different coffee machines.
• The shutdown made front-page news in The Times of London and The Washington Post.
• Krups refurbished the auctioned pot for free, and it brewed coffee in Der Spiegel’s newsroom.
• Since 2016 it has been on loan to the Heinz Nixdorf MuseumsForum in Paderborn, Germany.
• The 1998 April Fools spoof RFC 2324 defined the Hyper Text Coffee Pot Control Protocol and error 418, I’m a teapot.