The Easterhegg (also Easter(H)egg or EH) is an annual hacker event, created by the German Chaos Computer Club. Since 2001 the Easterhegg takes place during the Easter celebrations.
Most participants are from German-speaking countries, with others from the rest of Europe or further afield. The Easterhegg consists mostly of workshops with some lectures, with topics covering the whole spectrum from tech to culture and hackerspaces. Furthermore, Easterhegg is non-commercial and all the workers are volunteers.
References
Easterhegg Wikipedia(Text) CC BY-SA