Abstract
Networks of social activists traditionally lack financial and human resources, resulting in low interest in employing sophisticated IT. There are not many studies describing the development and use of computer systems for networks of social activists. Especially with regard to web 2.0 applications, it is interesting to analyze how social activists appropriate social web platforms. In this paper we describe the usage of a collaborative platform called "OpenESF" by social activists taking part in the European Social Forum. The results of this study will provide us with an understanding of the needs of social activists for effective computer support and highlight directions for the redesign of OpenESF.