I've done [email protected], [email protected], etc. I don't keep track of them carefully so I may pick the same name for two different sites.

It also makes it easier to pass off a fake realname! Hi I'm John Smith, [email protected]...

You can even pick a domain sound like a legitimate mail service or company, e.g. [email protected] [email protected]

All domains and addresses in this comment are fictitious - overlap with real domains is coincidental.