Browse your referrer logs? Have your own website? Then you're being targeted by Data Shaping Solutions Viral Marketing. Buy a campaign from them, and they'll spoof a referrer to your website so you'll see a clickable link to the customer in your logs. Advantages include not losing your account for being a spammer because the advertising isn't by email, and a robust technique the details of which can only be revealed if you contact them. "More and more people have their personal website with access to daily site statistics. Typically, internet services of any kind are good candidates for this type of advertising."
Christ. How long before my logs are as full of spam as my inbox? I've seen a few unusual corporate looking 'sites in there already. Is this form of advertising common? What's worse: Guess where I found the viral marketing link. Standard advertising loop. Find a trusted place; pretend to be part of that place and exploit the trust people have in it; support that medium and make it reliant on advertising; reduce expenditure so that place does nothing but the bare minumum to support advertising; more on to another trusted place.