I really like this mod, and in fact, you have gotten me interested in maybe using a fog machine like this for Halloween.

But I am not having much luck finding information about how they work. Do you have any good link which explains it? Specifically, as others have asked, what is it that actually ends up getting sprayed into the air?

Looks like the other ingredient is propylene glycol. Perfectly safe for people, but seems like over time, it can't be good for the machines or my house. I don't think I'll use it in the game room.

Using it outside for Halloween might be a go, though.