This paper focuses on the uses of Web 2.0 platforms by residents of favelas, urban slums in Brazil, in order to expand our understanding of what Web 2.0 can and cannot do in terms of social change. To explore this problem space, I draw on a 10-month ethnography in the favelas of Vitoria, Brazil to study slum residents’ Web 2.0 practices and engagements. I show how Web 2.0 afforded favela residents the ability to protest and cross social boundaries, but when that happened they faced something much stronger: social exclusion, police brutality against the blacks and poor, and limited civic engagement.