Another way to wind up on spam lists is by selling domains on forums that get indexed by search engine spiders (such as this forum). then the spam spiders 'read' the domain name listings on the search engine (or worse, directly on the forum) and put names plus '@' in from of it and presto, plenty of email addresses generated that wind up in the domain name's 'catch all' email account!
Because of this, I mostly list my names on forums this way:
.com names:
MyDomainOne
MyDomainTwo
MyDNThree
.biz names:
NiceBizNameThisOne
AnotherNiceOne
AndOnAndOnAndOn
Cheers!
Rob
(Of course, if a spam-crawler finds a list of recently reg'd domain names somewhere (through zone files, maybe), then your names may still wind up into one of their email address generating programs, resulting in spam...

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