I feel that that's not what email is for. Any communication method needs a return address, otherwise spam and abuse.<p>Email has two very distinct purposes, not 1, not 3.<p>1- federated pseudonymous identity protocol for internet(ip/http).<p>2- medium-length business time insensitive communication.<p>That's it.<p>This sounds like a free experimental product aimed at improving 1, but most service providers will either have to block it or face abuse from users of your domain.<p>What OP doesn't know yet probably is that they will not be the ones under dos/spam,rather they will be used to DoS, spam, simulate traffic, scam, etc...<p>Edit: the ToS outlaws spam, so it is possible they will cooperate with spam blacklist providers like spamhaus ( not sure how). Not sure how businesses will block the domain for acct creation, probably as a whole, Ive seen websites use a whitelist approach like gmail, or outlook.