A pinball or arcade cabinet -- but then who doesn't have at least one of these
If you are running toys (solenoids, flashers, etc) DOF installed and running (Look here
http://mjrnet.org/pinscape/dll-updates.html If you are running an arcade machine with MAME, perhaps DOF2DMD or Pixelcade, then you will not need a full installation of DOF, but it can't hurt if you do. Of course if, like me, your arcade machine has a Pinscape, Dude's Cab, Teensy, then you will need DOF.
At least one Pinscape Pico, LEDWiz, Pinscape, PacLed64, Ultimate I/O, PinControl1,
PinControl2, PacDrive, SainSmart, PinOne or Dude's Cab controller
board
If you want, a Teensy, Wemos or MX_Donny (or similar) setup for addressable LEDs in DOF
Keyboard input (or emulator) to your favourite pinball emulator