Spotted a bunch of referrer entries from this site, which appears to be a search engine. What made them stick out was their absurdity:
http://www.overture.com/d/search/p/nz/?xargs=02u3hs9yoazcuxLg0N81atTs8sSi%2B2Kcgtyi9IVipKy1TMSbdLzU0Hi2ZK5iTkpaWnJEWlFtsXGBoalRRnVlsn5jt6lxdnBFeFujkCOcitzy6JycxKLw2NKc70L0gKcvf0cXN0zCwsdHbWdlZ3AAMazz8l&Partner=netzero_yh_nzwebmail
A quick look at their web site told me all I’ll ever need to know about them:
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