Gilbert Beyer from Munich came to visit our lab. In Munich he is working on interesting projects that combine aspects of software engineering and human computer interaction in the group of Prof. Martin Wirsing. Gilbert participated in the pervasive computing in advertising workshop in Nara and we met there.
We discussed aspects of how to study and empirically evaluate larger and off-desktop interactive systems. Even though those systems differ significantly from desktop systems the book How to Design and Report Experiments by Andy Field and Graham J. Hole is still a good starting point.
Carting new territories is exciting and it seems that this happens currently in various areas. Historicaly it is interesting to look at Card's paper  for a useful design space for input devices - must read ;-). Tico Ballagas looked into a design space for mobile interaction in his PhD - also very interesting - if you do not have the time to read the thesis, have a look the book chapter . Over the last year Dagmar worked on a design space for the automotive domain, which is accepted at Automotive User Interfaces conference (auto-ui.org) and which will be published in September.
 Card, S. K., Mackinlay, J. D., and Robertson, G. G. 1991. A morphological analysis of the design space of input devices. ACM Trans. Inf. Syst. 9, 2 (Apr. 1991), 99-122. DOI= http://doi.acm.org/10.1145/123078.128726
 Rafael Ballagas, Michael Rohs, Jennifer Sheridan, and Jan Borchers. The Design Space of Ubiquitous Mobile Input. In Joanna Lumsden, editor, Handbook of Research on User Interface Design and Evaluation for Mobile Technologies. IGI Global, Hershey, PA, USA, 2008.