KMWin (Kaplan-Meier for Windows) is a convenient tool for graphical presentation of results from Kaplan-Meier survival time analysis. The programme is based on the statistical software environment R and provides an easy to use graphical interface. As an introduction, see http://dx.plos.org/10.1371/journal.pone.0038960#s2.
Creates a data density plot of a 2 dimensional data distribution.
...The program uses sum of reciprocal squared distance to calculate density at each point, with a smear factor to prevent points going to infinity. The smear factor also controls the amount of clustering.
There are several options for colour output. Input is via a csv (comma-separated values) file.
Now there's a nice GUI built in Baby X for Linux and Windows