VizieR (http://cdsweb.u-strasbg.fr/cgi-bin/VizieR) is a collection of around 2400 catalogs (1800 already available on-line) that can be queried either by the specific entry on it, by author name, a set ofkeywords that specify the object, the wavelength of interest and the mission or through a map based on a neural network analysis of the keywords associated with the catalogs. Since having Hipparcos on-line in May 1997 the use of VizieR has increased exponentially.
VizieR is a cooperative endeavor between the CDS, the Astronomical Data Center in the US, the Russian Academy of Sciences' Institute for Astronomy (INASAN), the National Astronomical Observatory of Japan, the Beijing Observatory in China and the Indian Inter-University Centre for Astronomy and Astrophysics (IUCAA). The CDS created a standard which is followed by these data centers and (most importantly!) by the journals in the publication, presentation and distribution of the data.
Future enhancements include links to SIMBAD and other external archives.