The Global Hack for Good, which is organized by Refugees United, is planning a series of "hackathons" - a weekend-long marathon of developing applications on mobile networks - to be held on three continents, on three separate weekends, but all are working toward the same goal of making re-connection easier.
The first hackathon will be in Cairo, Egypt, on 31 May-1 June. Then, a new batch of developers will gather in San Francisco, USA, on 7-8 June, and the third part of the Global Hack for Good will be held in Nairobi, Kenya, on 15-16 June.
Ericsson is backing the effort.
http://www.meetup.com/hackforgood/