Digital Ocean should provide a optional "Powered By" logo/link. If registration is successful then the user should be given a reward/discount.
We have logos and badges that you can use here:
And when the new control panel launches hopefully next week it will have a referral program so that you can easily refer friends and get credits.
Because we have a separate request in UserVoice for the referral program which has more votes I'm going to close this one.
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