In this paper we briefly examine the use of Twitter in Iran, Tunisia and Egypt during the mass political demonstrations and protests in June 2009, December 2010 and January 2011 respectively. We compare this usage with methods and findings from other studies on the use of Twitter in emergency situations, such as natural and man-made disasters. We draw on my own experiences and participant-observations as an eyewitness in Iran, and on Twitter data from Tunisia and Egypt. In these three cases, Twitter filled a unique technology and communication gap at least partially. We summarize suggested directions for future research with a view of placing this work in the larger context of social media use in conditions of crisis or social convergence.