I use [vendor name]@[mycustomdomain].com which is a catch-all email, [anything]@[mycustomdomain].com goes to my inbox, so if I use something like disney@[mycustomdomain].com and then I have to talk to someone on the phone about an order and they ask for my email address, they invariably get confused and think I work for the company or something like that. Then I have to explain that I use the company's name in the email address so I can track who is selling my email. They don't understand it but I'll keep explaining it until they just accept it and move on.