Here in the UK, there has been a pretty large storm about BT's trials (and proposed implementation) of the obnoxious Phorm system in which all users' web browsing sessions are intercepted and data extracted in order to deliver targeted advertising. A No 10 petition has collected a large number of signatories, and several websites have been set up to explain the problems associated with Phorm and to campaign against it. See isphormlegal for example.
Over in the USA, a company called NebuAd have been playing the same game. Working with several ISPs, they have been playing fast and loose with customer rights. Now it seems the chickens may be coming home to roost. Ars Technica reports that a class action has been launched against NebuAd and its ISP collaborators. As Ars Technica reports: