GNU R package for Visualizing Multivariate Data

 Scatterplot3d is an GNU R package for the visualization of multivariate data
 in a three dimensional space. Basically scatterplot3d generates a scatter plot
 in the 3D space using a parallel projection. Higher dimensions (fourth, fifth,
 etc.) of the data can be visualized to some extent using, e.g. different
 colors, symbol types or symbol sizes.