In recent years, the deteriorations of living habits like immobilization or unhealthy diet are becoming serious social problems in many developed countries. Even if we know the importance, it is difficult to change our undesirable habits and to maintain a desirable lifestyle. This study demonstrates a concept called ambient lifestyle feedback systems to be used to motivate people to change their undesirable habits to improve their lifestyle. In the concept, aesthetic and empathetic expressions reflect the feedback of the user's current behavior to the user. When keeping desirable habits, the user is offered with a feedback expression designed to boost his positive emotion. When turning to undesirable habits, the feedback expression is changed to increase the user's negative emotions. In this paper, we present brief overviews of four case studies of ambient lifestyle feedback systems, and discuss several findings that we while designing and evaluating the case studies. Future directions will also be discussed.