This paper, focused primarily on UK data and debates, considers the potential significance of travel time use within past, present and future patterns of mobility. In transport scheme appraisal, savings in travel time typically represent a substantial proportion of the benefits of a scheme—benefits used to justify its often enormous financial costs. Such benefits are founded on the assumption that travel time is unproductive, wasted time in-between ‘real’ activities and which should be minimised. Travel demand analysis treats travel time and activity time as separate, albeit acknowledging an interdependency. The paper challenges these approaches by exploring how travel time can be, and is, being used ‘productively’ as activity time, and what enhancements to time use might be emerging in the ‘information age’. Such undermining of the division between activities and travelling, and between activity time and travel time, may have major implications for future levels of mobility, for the modal distribution of travel, for the validity of current transport appraisal methodology and for the analysis of travelling within the information age. These issues are considered.