Stalker is a collective of architects and researchers connected to the Roma Tre University who came together in the mid-1990s. In 2002, Stalker founded the research network Osservatorio Nomade (ON), which consists of architects, artists, activists and researchers working experimentally and engaging in actions to create self-organised spaces and situations - spatialagency.net 
YOUTUBE Ty1Tys-IpSs Lorenzo Romito (Stalker) - Tactics For Entropic Environments