I think it's just as Pickle said, they're sent out by a computer, which basically sends emails to every combination of letters.
In other words if your name and email addy were:
[email protected]
The computer would send emails out to:
[email protected]
[email protected]
[email protected]
and so on.
Then it would start again using double initials:
[email protected]
[email protected]
[email protected]
and so on.
Continuing in this fashion, it would eventually send one to
[email protected] and you of course would be the unfortunate recipient.
That said though, I have received many emails that don't even have my name on them at all, but just a variation of it. I'm still puzzled as to how these reach my Inbox. I did read somewhere how they are able to do this but it was way over my head!
I keep getting emails from a "lawyer" in Nigeria, telling me that someone of the same last name as me has died tragically in a plane crash and they'd like to deposit $26,000,000 (US dollars) into my bank account! Yeah right! they must think we've just got off the banana boat.