OPeNDAP

OPeNDAP (Open-source Project for a Network Data Access Protocol; wikipedia entry here) is a framework that simplifies all aspects of scientific data networking (quote from OPeNDAP document). It makes local data accessible to remote locations regardless of local storage format. OPeNDAP also provides necessary data transformation tools.
I have seen some applications to GIS related projects. One example is the one by Northeast Fisheries Science Center - Oceanography Branch. The researcher claims to be able to generate dynamica GIS maps in shorter time than when using predefined SQL statements in the traditional way.
According to wikipedia, "OPeNDAP is widely used by governmental agencies such as NASA and NOAA to serve satellite, weather and other observed earth science data." Furthermore, "Compared to ordinary file transfer protocols (e.g. FTP), a major advantage using OPeNDAP is the ability to retrieve subsets of files, and also the ability to aggregate data from several files in one transfer operation."