Bitbounce - Charge unsolicited email senders a cryptocurrency fee
Tremendous - Tremendous is a customer and employee loyalty platform that allows companies to reward their customers for surveys promotions and referrals.
21 Lists - Send and receive targeted, paid microtasks
Giftbit - Buy, send and track digital gift cards for your reward and incentive programs.
Bitbounce-Credo - A cryptocurrency spam solution
Rybbon - Send digital e-gift cards as marketing incentives or rewards with Rybbon, which integrates with Marketo, HubSpot, SurveyMonkey, and Qualtrics.