I always wondered how fun it would be for like a rival companies to dick around with account info. Say for example someone registers to Warcraft with <Accountname1> and <password1>. And then the admins at Blizzard decide to try that log in on Square-Enix or other random websites just to see how many folks reuse the same password.

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Ever since I got lastpass a few years ago I've been using completely different passwords for everything. I'm utterly in love with LastPass.

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I remember registering my Blizzard authentication to one of my really old phones (I'm thinking iPhone 4?), and then trashing it and never really recovering it. But was able to reset the authenticator from the website because it was registered to my phone number and not actually my specific phone. I don't remember all the details other than it was stupidly easy to solve. And I was good to go without any issues.