Operation Flashpoint: Community Masterserver
On 31st of May, 2014 (effectively on 31st of July), GameSpy servers were closed. As a result, the in-game browser of OFP/ARMA:CWA stopped working. Thanks to Poweruser's effort it was possible to overcome this difficult situation. Poweruser created a program that alternates the former GameSpy masterserver by a new one that is hosted by PFC (Polish Flashpoint Community). The PFC masterserver was hosted from 31.05.2014 till 31.12.2016. A new community masterserver has been launched - more about it here.
Community masterserver is the main source of information for OFPMonitor - a program that allows to join OFP/ARMA:CWA multiplayer servers.