Main OtherSoftware
From OpenFOAMWiki
In addition to the officially supported tools (especially paraFoam) there is a number of other software that make life with OpenFOAM easier.
1 Pre-Processors
For people who need a bit more complicated grids (of course you can always do it with blockMesh.
Very good overview of free and commercial mesh generators.
2 Post-Processors
Looking at your results in many colorful ways.
2.1 OpenDX
The mighty OpenDX is for those who think that Paraview is too simple (and not powerful enough).