The ubiquitous presence of web-based services and tools for communication, collaboration and learning raises the question whether and under what conditions these tools have the potential to foster creativity. In this paper we first elaborate a person-centered notion of creativity. Taking this notion into account, specific functional and non-functional requirements on web-based tools are given from a software engineering perspective. Subsequently, we propose preconditions for creative settings and illustrate them by sample scenarios. It will be argued that creativity - in a person-centered sense - can be supported by web-based tools only, if certain inner and environmental conditions are met, such as openness to experience, a non-judgmental attitude, and freedom of symbolic expression. The paper is intended to support decisions pro and contra the use of web-based tools on the basis of investigating both the human and technological conditions under which we are most likely to be creative.