I think this sounds like a good idea but the registration fee is much too high. I think the fee should cover Spamhaus' costs to administer the program - but not be so high that only large companies can afford to register with the program (lest we forget that many of those same large companies send out a lot of unsolicited email). Perhaps a longer term registration would work - something like $500 for 5 years.
I we could get a system in place that curbs even 50% of the spam, I would gladly pay a fee like that.
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