Presentation given at the Tesla Symposium 'Visions and Imagination: Advanced ICT in Art and Science', organized by Gordana Novakovic at the Department of Computer Science of UCL on 24 November 2007, and funded by AHRC Methods Network.

ICT systems are moving outdoors and becoming ubiquitous: the devices we carry with us provide us access to applications and communications (almost) anywhere and at (almost) anytime. At the same time, huge effort is being made to map the real world: through services such as Google Earth and Microsoft Virtual Earth we explore detailed 3D models of the world around us. However with the combination of these systems we can start to interleave the virtual with the physical and reveal the nature of the physical in ways that haven't previously been possibly.

In this talk, Anthony Steed gives an overview of a few recent technology-led projects that have interleaved the physical and digital in new ways. These include making 3D pollution maps from mobile tracked sensors carried by commuters; realising location-based services which exploit the physical structure of the urban environment; augmented reality system that map virtual information into real places and telecollaboration between virtual worlds and real spaces.