Inflatable ones have been around for a long time. They have a hole for your face and hollow cavity to breath inside. I bought one on AliExpress few years ago fo

Inflatable ones have been around for a long time. They have a hole for your face and hollow cavity to breath inside. I bought one on AliExpress few years ago for about 10 bucks. Still haven't tried it yet, but they are supposed to be for sleeping on trains, etc.