Are you serious? No-one in their right mind would actually help anyone find ways to spam Elgg sites. Quite the contrary. :)

Lol.

Just to turn the corner on this thread a bit...

Are ad servers a way of introducing spam if you run your own? 

Is there a way to use them in Elgg that is a healthy way to add some monetization for a network?

I ask as a new person looking at this subject for a project and was thinking ads, self hosted and only carrying those directly related to the project theme, would be a positive thing. 

Willing to learn though!

@keith I understand that  "Ad serving is the technology and service that places advertisements on web sites." if  that what you are looking for then elgg is able to accommodate other ad serving software to run ads on the elgg site. Look at a plugin in I had developed and see how elgg can work with called Gutwa - Elgg Ads Management System  https://elgg.org/plugins/1609647