How it works
There are two ways the ad-block technology works and ways for companies to detect it.
Firstly you have static images, jpegs and the likes. The adblock software has a blacklist and doesnt download content from those domains/links. Companies can detect this by matching page requests with image requests, and hinder future requests from the same session
Second is the more active content, like flash. Because of built in scripting functions, a n onload script can then request something else, alerting the company that the ad has been seen. Again sessions contrio
So how to combat this. Virtualisation technology. Have a little box to display all the ad content at will, but fail to connect it to a screen!! woops. It should be quite undetectable, as really all your doing is ignoring the content rather than blocking it. Does add to the bandwidth bill (on both sides might i add )