Lambda the Ultimate

another language for plotting, looks to be especially good for/focused on climate visualizations (as is to be expected being maintained by the national center for atmosperic research, one of their visualization and enabling technologies http://www.vets.ucar.edu/software/index.shtml). supports working with netCDF, HDF, Grib, and CCM History Tape data formats.
Has some nice features regarding variables, including call-implicit instantiation and undefinition of variables, although I can't see how these features per se help them in the language's ostensible analysis and visualization of data goals (as opposed to just being aesthetically pleasing features and generally helpful)