Any use for coins/tokens of defunct projects like Synereo/Hyperspace (AMP) and others?
Just a display in your ETH address

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If the project/crypto is failed, there is nothing you can do about it but to just store it in your ETH wallet and do nothing. If you can sell it in an exchange where there is volume in it then you are very lucky with it. I have been in the bounty campaigns for like a year I think and I have received many tokens that until now doesn't have value. There are some who has value though but you can't sell it because there is no volume in the exchanges so for me it is considered a failed token.