I've just had a PM from a member who received an email, apprently from me, and suspicious-looking, possibly spam or virus.
Similarly I'd received an email apparently from Coral's six-year-old daughter, which crashed my browser when I opened it.
Since then I've looked closer at some of the 'postmaster' returns in my mailbox - returned mail I'd never sent, naturally - and found email addresses for two other members of this site or the Vault. The only thing some have in common is a link to a possibly Chinese electronic goods site.
So, thanks for the information, and be careful what you open in your mailboxes.