From Smartspace, a tale of new levels of interactive infrastructure:

Recently news came out that the city of Middlesbrough in northeast England have added a backchannel to its CCTV system, allowing police to not only spot bad behavior, but to issue verbal corrective measures on the spot. As concern about so-called anti-social behavior grows in Britain, both local and national governments have taken additional steps to curb hooliganism, however it is defined, and put offenders on notice more rapidly. One step has been on the spot fines, but this new system takes "on-the-spot" a bit further, allowing the "city" to talk back to its citizens in real time.

While this trend will surely spread, it portends more "active" infrastructure that can interact, encourage or dissuade, even punish, users.