Tioga is a Ruby library for scientific plotting which uses pdfTeX as a renderer. This allows production of publication quality vector format graphics with almost any (La)TeX text/formulas appearing in the image:
Example of Tioga visualization: File:Http://www.kitp.ucsb.edu/~paxton/tioga jpegs/opacity eos.jpg
Tioga is limited to 2D visualization. It is particulary useful for traditional function plots, 2D fields in false color, and contour plotting.