Cytospec is free software package useful for flow cytometry data analysis. It includes both traditional listmode data analysis techniques available in most commercially available packages but it also provides PCA analysis in an easy to use application. Further, there are dozens of useful options such as ability to save gated datasets to new listmode files, ability to add or subtract noise for a data set, spectral flow cytometry algorithms, and a plethora of other useful utility features. Reads most flow cytometry data types.
Latest stable release
You can use the 5 color listmode file if you want to play along.