[PaulHoule]

I understand that the email server has digression on what to do with the local part of the email address. For instance a mail server could take mail to [e-mail] and put it in the "wildcard" box.

I was a qmail fanatic circa 2001 and back then qmail was often configured to put emails to "[e-mail]" to the unix account you and also send "you-*@yourdomain.com" to the you account (anything that starts with "you-")

Of course you can use this to tag email address so if you subscribe to Facebook using "[e-mail]" then emails from Facebook are sent to "hn".

I think the people at gmail thought this was a good idea but that it was better use + instead of - so there you go.