I am Hack Sparrow
Captain of the Internets.

plugin-container.exe making connections to unknown servers

Are you seeing a strange process named making connections to some unkown server or website? If you are using Firefox 3, it is most probably the process used by Firefox for running it's plugins. A decision was made to make the Firefox plugins run in a separate process to keep the browser working even if the plugins crashed - inspired by Google Chrome. So the connections to those websites or server ...