Who watches the watchmen?

Just found this interesting documentary by Henry Porter on the use of CCTV in Britain and the rise of a surveillance state in response to the "war on some terror".
As a film maker, 21st century video voyeur, and armchair civil libertarian this subject fascinates me.
The idea that we'll be safer if we allow governments, corporations, and now individuals to monitor everyone else certainly sets off alarms in people concerned with personal privacy.
Is there a balance to this Orwellian idea of a creepy Big Brother?
Can it work in the opposite direction?
Do citizens have the power to turn their own electronic eyes and ears back on those "guardians of our best interests"?
I'll try to find some answers to these questions in the near future and post them here.