Coffeeman 500's Useless Box – Multi Switch project is an open-source hardware project that's an ambitious variant on the beloved "Useless Machine" — 2010, 2010 (Lego)), 2010 Political edition), 2011 (HOWTO), 2012 (politics), 2013 (fancy), 2013 (advanced) (vs human), 2016 (most useless), 2017 (vs twisty vase).
In Mr 500's implementation, the useless machine has three switches, and it remembers how you switched them: when you tick them off, the machine unticks them in the same order that you switched them.
It's 500's first-ever OSHW project, and it's a really fun one! Here's a Reddit /r/electronics thread where they're planning more ambitious variants; here's the code, and the schematics.
Multi-switch Useless Box Is Useless In Multiple Ways [Richard Baguley/Hackaday]
