This study explored the possibilities to design interactions that evoke user interest. On the basis of appraisal theory, it was predicted that interest is evoked by a combined appraisal of novelty complexity and coping potential. Because the role of novelty-complexity is well-documented (i.e. a product must be appraised as novel and/or complex to be interesting), the study focused on the role of coping potential: the degree to which one appraises oneself to have sufficient skills, knowledge, and resources to deal with an event. Two workshops investigated how the interest appraisal manifests in the context of human-product interaction in terms of appraisal questions and related product qualities. The findings were used to develop three prototypes of interactive music players. These were identical in terms of appearance, but different in terms of coping requirements during product use. The main study measured the appraisals and emotions of people using the prototypes, using both self-report and behavioral measures. The results indicated that along with noveltycomplexity, a high level of appraised coping potential is necessary for experiencing interest. When coping potential was appraised as low, the respondents experienced negative emotions such as annoyance instead of interest.