On Tuesday morning Steve Benford presented the entertainment interfaces keynote. He is interested in how to use computer technology to support performances. Steve works a lot with artist group, where the University is involved in implementing, running and studying the experiences. The studies are typically done by means of ethnography. The goal of this research is to uncover the basic mechanisms that make these performances work and potentially transfer the findings to human computer interaction in more general.
I particularly liked the example of "Day of the figurines". Steve showed the video of experiences they created and discussed the observations and findings in detail. He related this work to the notion of trajectories , . He made the point that historic trajectory are especially well suited to support spectators.
Some years back I worked with Steve in the Equator and we even have a jointed publication  :-) When looking for these references I came across another interesting paper - related to thrill and excitement, which he discussed in the final part of the talk .
PS: we had a great party on Monday night but the attendance was extremly good :-)
 Benford, S. and Giannachi, G. 2008. Temporal trajectories in shared interactive narratives. In Proceeding of the Twenty-Sixth Annual SIGCHI Conference on Human Factors in Computing Systems (Florence, Italy, April 05 - 10, 2008). CHI '08. ACM, New York, NY, 73-82. DOI= http://doi.acm.org/10.1145/1357054.1357067
 Benford, S., Giannachi, G., Koleva, B., and Rodden, T. 2009. From interaction to trajectories: designing coherent journeys through user experiences. In Proceedings of the 27th international Conference on Human Factors in Computing Systems (Boston, MA, USA, April 04 - 09, 2009). CHI '09. ACM, New York, NY, 709-718. DOI= http://doi.acm.org/10.1145/1518701.1518812
 Benford, S., Schnädelbach, H., Koleva, B., Anastasi, R., Greenhalgh, C., Rodden, T., Green, J., Ghali, A., Pridmore, T., Gaver, B., Boucher, A., Walker, B., Pennington, S., Schmidt, A., Gellersen, H., and Steed, A. 2005. Expected, sensed, and desired: A framework for designing sensing-based interaction. ACM Trans. Comput.-Hum. Interact. 12, 1 (Mar. 2005), 3-30. DOI= http://doi.acm.org/10.1145/1057237.1057239
 Schnädelbach, H., Rennick Egglestone, S., Reeves, S., Benford, S., Walker, B., and Wright, M. 2008. Performing thrill: designing telemetry systems and spectator interfaces for amusement rides. In Proceeding of the Twenty-Sixth Annual SIGCHI Conference on Human Factors in Computing Systems (Florence, Italy, April 05 - 10, 2008). CHI '08. ACM, New York, NY, 1167-1176. DOI= http://doi.acm.org/10.1145/1357054.1357238