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By reading emails you earn MAIL tokens and have a chance to win the bonuses they refer as "shaky-shaky" (because the window shakes when you get them).

You can use the MAIL tokens to send emails of your own. But pile them up, it's no use to send to less than 1000 people, in my opinion. 1 MAIL token = 1 person receiving the email.

You should also upvote emails after you click the link and see the page that opens, but you don't have many upvotes available without staking more CTP on Listnerds.

As I said in my post, it's better to be upgraded. And much more profitable from what we have seen so far.