Heres a usefull gmail trick:
You email addy is
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we want to join a site thats going to potentially send us unwanted emails or a site we have joined before and blocks us because we need a unique email addy.... so we use this adress:
(you need an account to see links)
Now we make a new label "neo" and then add a new filter:
To:
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Apply the label: neo
Now any email from that site gets sent to our "neo" folder. Also we can use it on a few sites to allow us to use the same email adress (where "+" symbol is not detected). Never tried it on neopets to be honest...