Hi,
the picture on the COSMOlogic web site has been created with the OpenGL viewer of COSMOtherm
http://www.cosmologic.de/ChemicalEngineering/cosmotherm.html and visualizes the screening charge density on the molecular COSMO surface.
The same OpenGL viewer for orbitals, densities, electrostatic potentials, vector fields, etc. will be part of TmoleX 2.
In the meantime I would also recommend gOpenMol like Mikael.
Turbomole 5.10 can also print cub files, so also other programs like VMD can be used.
Uwe