Why do some people get so much spam?

This is one of the great puzzles of the Internet age, I think, the question of why some people get so much more spam than others. I know that I have multiple accounts on Gmail, for example, and some of them get a lot of spam (100 or more daily) while others seem to be completely off the radar and receive zero spam.

My theory is that there are two key factors: where you use your address, and whether your email address is an easily guessed "dictionary" word or phrase.

The worst case scenario is that you're "john.smith@gmail.com" and that you use that email address to register on a wide variety of different sites and services. That's a recipe for trouble.

While most of the sites you encounter on a daily basis are probably clear and honest, it's not hard to imagine how the sequence of events might go: you register on legit site A, which sells its mailing list to reasonably legit site B for a one-time mailing. It generates revenue and helps keep the company in business. Site B sends out its one-time mailing, but also "accidentally" keeps a copy of the list for a second mailing that it never actually sends.

A few weeks later, however, company C contacts company B and expresses an interest in buying any sort of qualified list they might have, for big bucks. What the heck, right, it's a good offer, so company B sells it to company C, who then resells the list to spammers at $1/addr in mass.

Now with just a few hops, your email address has traveled into the database of people who are perhaps sending still quai-sorta related offers. But they have a partner company that is focused on the worst kind of spam and, well, $0.10/address is still revenue, right?

And so it goes...

The other side of this is that there are companies, though it's kind of hard to believe, that send email to millions of variations of names, words, and common additional sequences, hammering big public servers like "gmail.com". If your account is "dave@gmail.com" you're just going to get more spam than "dave12taylor34@gmail.com" would (no, that's not my addr!) because the former is trivially guessable and once a spam message is sent and doesn't bounce back as "recipient unknown", guess what? You get a lot more. Then a LOT more.

There are likely additional reasons that might explain why your brother gets so much more spam than you do, but I'd just suggest that, for now, you don't tell anyone about your luck, in case you mess things up. :-)