Web-cam crime fighting

Taking a break from my to-do list, I decided to check cnn.com. There I found an intriguing article about web-cam crime fighting. A home owner had installed a web cam at her home after the home was burglarized. One day while watching the camera feed from her workplace, she witnessed two men robbing her again (they also grabbed a snack from her fridge). She called the police and they busted the perpetrators.

Here's a community policing idea -- what if we install web cams around the city's trouble-spots and then distributed the feed via the city's web page. We could all pitch in to monitor happenings around town. Whenever a resident is curious about activity happening across the street -- say, the shadows moving in the dark over in the park after it is closed -- she or he could log onto the site and get a look. If something fishy is going on, a call could be made to dispatch.

I know, I know -- this idea sounds rather "big brother." But, if the city posted notices (e.g., Notice: This public space may be monitored by video surveillance) and the cameras focused only on public spaces, I think I'd be comfortable with the idea. I might even give up my trashy reality TV shows to watch the realities of our streets.

What do others think? What would be the hardware and software needs of something like this? Are there wireless web cams that would make it possible to move the cameras wherever they are needed? What about legality?