MAP Home Page (Popularity: )
http://map.gsfc.nasa.gov/ MAP is a MIDEX class mission, selected by NASA in 1996, to probe conditions in the early universe. MAP measures temperature differences ("anisotropy") in the cosmic microwave background radiation.
Sloan Digital Sky Survey (Popularity: )
http://www.sdss.org/ A dedicated 2.5 meter telescope which uses sensitive electronic light detectors to systematically map a quarter of the sky, building a catalog of celestial objects, galaxies, and quasars.
MACHO Project (Popularity: )
http://wwwmacho.mcmaster.ca/ Primary aim is to test the hypothesis that a significant fraction of the dark matter in the halo of the Milky Way is made up of objects like brown dwarfs ...