I'm sure there are people who use electric cords and whatnot, but there are specifically devices made to provide these shocks safely (as much as they can be safe; they do come with warnings--which I know from reading about them in catalogs, not from ordering them myself, LOL!).

alexandra, in case I didn't come across as such, I am not putting you down for your feelings or beliefs on this topic; I'm just sharing my views, and not saying you're wrong or anything.