Friends of the Earth Netherlands has offered "Oily Mary" cocktails, containing polluted water from the Niger Delta, to Shell shareholders who are meeting near The Hague. The stunt was designed to force the Anglo-Dutch oil multinational to clean up its act in the Niger Delta.

Leaking oil pipelines make it one of the most polluted areas in the world. Shell accuses the local people of tapping the pipelines. But Friends of the Earth Netherlands say the spills are caused by poor maintenance.

For years, the group has been waging campaigns to draw attention to environmental problems. Now, they are beginning to use social media, too.