They're a lot of fun if you can get the film. Some company reverse engineered it and then went out of business, but I think there are still options if you're willing to pay $2 a photo.
Go for it. Keep in mind, theres two types of film now though. "Retro" and "modern". Don't remember the classifications. Either way, modern doesn't work in retro cameras cause there's no built in battery.
Box should make it clear, but I know I grab without reading the box all the time. Figures I'd give a warning.
I have a Kodak Brownie here somewhere. I've never tried using it, but it should work - the shutter spring is in place and functional. The mirror for the viewfinder is messed up, too, so I might not be able to frame the shot correctly either.