Benjamin Gaulon, aka Recyclism is an artist, researcher and lecturer at the National College of Art and Design in Dublin. In his 2.4 GHz project he uses a wireless video receiver to hack into 2.4 GHz wireless surveillance cameras placed around the city and displays this footage back to the observed at street level.
According to Benjamin he is pursuing three major initiatives within the project. First, he's traveling around Europe on his own to collect and publish footage captured using his receiver device (As seen below). Second, he is placing the broadcasting devices on street infrastructure to reveal to the public the presence and ability to capture this type of monitoring footage. Finally, he is holding a series of 2.4 GHzworkshops that invite local residents to explore their own neighborhoods and cities to search for 2.4GHz surveillance video signals and map these online using a Google map for others to explore.
An additional element of the project brought up by the artist is that not only are surveillance cameras using this type of technology but it is also being integrated into consumer products like home baby monitoring devices. Many people may not be aware that they could be broadcasting this signal out to the world.
You can learn more about Benjamin's work and the project details at: http://www.recyclism.com/