Henry Porter, one of the few journalists to "get it" has an excellent article today about how people are being lifted by the police for photographing things - cycle paths, derelict buildings, railway stations and the like. They are then whisked off to the police station and their fingerprints and DNA taken. As our Henry says, something really has to be done.
My idea would be to have a "Photograph a Potential Terrorist Target Day", in which everyone goes out with their cameras and snaps away at any state-owned building. It doesn't actually have to be a terrorist target, any state owned building would do, but the point needs to be got across that this kind of behaviour is normal and acceptable and should not be an excuse for the police to meet their arrest targets by simply lifting people of the streets.
In fact, while we're about it, maybe we should start photographing state officials at work - including particularly policemen.