Swiss artist and designer Jürg Lehni celebrates the 20th anniversary of his seminal robotic drawing machine, Hektor (2002), in a commemorative Twitter thread. “Imperfect and full of character,” the hanging computer-controlled spray-paint plotter drew at transmediale, Design Museum London, and the MoMA, and remains a DIY marvel for its time: “edged circuit boards, assembly-programmed microcontrollers—we did everything by hand,” Lehni notes about making in the pre-fab era.

While researching the CO2 footprint of the Ethereum (ETH) cryptocurrency chain, media artist Kyle McDonald discovered ‘graffiti’ early miners left in ETH blocks using the “extraData” field. “One miner operating in 2016 decided to tell a story: one word per block, over 2.5 months,” McDonald writes on Twitter. “Maybe one of the slowest monologues ever” was mined over 129 blocks for 648 ETH and had a happy ending: “it looks like they cashed out early this year, for around half a million USD.”