[Sean Hodgins] creates a volumetric OLED display.
[Naomi Wu] creates a cyberpunk ultrasonic microphone jammer that uses ultrasonic transducers to jam nearby microphones.
Source code and design files are open source and available on GitHub.
[Sam Underwood] is working on an experimental bellows instrument.
[llvllch] creates a daily basic-bitch quote machine.
[Chris Courses] creates an automated water dispenser
Though the details are light, [s3msify] creates an automated drink mixer.
[MUDA-ZUKURI] creates a desktop machine that blows a plastic bag in the wind.
[@WillowCreative_] shows off a wolf head assembly
[Sarah Spencer] and [John Spencer] create an open source hardware automatic thread color changer for knitting machines.
The circuit board, design files and source code are available on GitHub. They also have some blog posts with more details on the machine and build.
[@Coelacant1] creates the start of a protogen mask and suit.
The mask with a diffusor on can be seen in a later tweet.