Marla's point about cavitation spooked me a bit. I had net positive suction head come up in my homework in chem. eng. design, which describes safe pump inlet pressure and vapor pressure of gases to avoid cavitation during operation. Now if only this knowledge helped me know useful things like cosplay mask vaporizer schematics.
EDIT: I think you guys were on the right track with an e-cigarette vaporizer. Probably a small battery-powered vaporizing chamber possibly filled with propylene glycol or something and may even be operated by a button or switch. If he kept enough of the apparatus intact some of them operate when you inhale. I'm a little surprised you guys didn't mention "the right to be forgotten" on the internet that's going on in the European Union. Information has already been revoked using that legislation, but hilariously the articles can still be found by doing searches for the comments on the articles instead.