Wikipedia
Gadu-Gadu
Gadu-Gadu ( Polish for "chit-chat"; commonly known as GG or gg) is a Polish instant messaging client using a proprietary protocol. Gadu-Gadu is the most popular IM service in Poland, with over 15 million registered accounts and approximately 6.5 million users online daily. Gadu-Gadu’s casual gaming portal had some 500,000 active users at the end of March 2009. Users send up to 300 million messages per day.
Gadu-Gadu is financed by the display of advertisements. The developer is based in Warsaw, Poland but the company is wholly owned by the South African media giant Naspers.