A piece designed to fit the
Crane "Drop Shape" Cool Mist Humidifier. With this in place, it resembles an egg from a certain movie about aliens. Turn the humidifier on and smoke will boil out the top. You can shoot green lasers through it, or just look at it really closely through your space helmet.
The smile on your face will make you want to give this thing a big hug once you see the final effect.
NOTE: Some Drop humifiers may be about 2-4mm wider, causing this to be a tiny bit too small. The best solution it to use a small amount of epoxy or other material to bulk up the rim of the print so it rests comfortably on top of your humidifier.