I use a CPAP machine (for sleep apnea) for the last 15 years (it changed my life)
normally i don't use a humidifier, but lately the weather her is so dry that i now need one.
I used to have one, it is a very simple device, so i decided to make one.
I used a standard glass jar (jam) and made the closing lid withe the hose connectors
I added a sealing ring (printed in flexible filament) and a coupler for the extra hose (i cut a broken hose)
MakerBot Replicator 2
even with 100% infill the printed lid is not watertight so i covered with E6000 glue and let it dry for several days outside (the glue has a strong smell)