I think I can speak to this topic.

I've been using "social networking" to promote my site on Myspace.com. My site is BestMyspaceProfiles.com so it fits to market this way.

I've found that having Myspace Whores (people with thousands of friends) advertising your product results in the same type of traffic as a decent Google Adwords campaign would. I've found that about 1% of the friends will respond to a bulletin post. So, to reach 100 people will require 10,000 friends.

The trick is to have something that others will want to pass on to their friends and at the same time will promote your product. Humor seems to work really well on Myspace.

Tyler