rgeos - an R wrapper for GEOS
by rundel for R Project for Statistical Computing
At present there does not exist a robust geometry engine available to R, the tools that are available tend to be limited in scope and do not easily integrate with existing spatial analysis tools. GEOS  is a powerful open source geometry engine written in C++ that implements spatial functions and operators from the OpenGIS Simple Features for SQL  specification. rgeos will make these tools available within R and will integrate with existing spatial data tools through the sp package .