These (the dot and underscore separators) are a great solution, because when the spam-happy-marketroids try to get the webdevs to intentionally implement broken email address validation, they can point out all the corporate email addresses which are by-policy of the form "firstname.lastname@domain.tld"…
Yeah, so much for RFC2822. Oh well, apparently, some spammers are clever enough to grep the emails with "+" and throw away the obvious additional portion.
