What's the best cold email you have used/seen and do they still work???

Don't send a cold e-mail on your first message. Just send a question. Something like this: "Hello, This is my first contact with your company, so just a quick question, please: Who would be the correct person to talk about XYZ in your organization? I ask on behalf of ZYX. Kind regards, Me" It is a genuine question, so it is reasonable to send you an answer. You clearly identify who you are and what you want to achieve, so your next letter will not be "that" cold. Hope this helps.