SETI Institute - nonprofit corporation engaged in research and educational projects relating to the study of life in the universe. Site incudes news, project summaries, and FAQ.
SETI@home - scientific experiment that uses Internet-connected computers in the Search for Extraterrestrial Intelligence (SETI). Users participate by running a free program that downloads and analyzes radio telescope data.
SETI League - grass-roots, nonprofit, member-supported organization devoted to the Search for Extraterrestrial Intelligence.
The SERENDIP Project - ongoing scientific research aimed at detecting radio signals from extraterrestrial civilizations and using the Arecibo Observatory in Puerto Rico.
NASA Astrobiology Institute - conducting interdisciplinary research on the multifaceted issue of life in the Universe and its cosmic implications.
Arecibo Observatory - world's largest single-dish radio telescope; located in Puerto Rico.