I haven't tried a real zapper, but I know there is definitely some killing power in electromagnetic fields. Immediately after my amalgam removal I became sensitive to electromagnetic fields, got chest pain and excessive salivation when sitting in front of computer screens. It happened everytime I sat in front of a computer screen, and the symptoms faded away when I went away, so I'm not imagining here. I also use headphones (which are much more powerful than computer screens) to successfully chelate/kill out something, but what is it? It's likely candida. The foamy salivation is a sign of that (for me at least). So I guess you can also zap with just headphones if you're lucky.