This is a screen shot of VisAD. It shows an application for collaborative analysis of GOES satellite sounding data. This is a typical spread sheet user interface that can be created with VisAD. The surface in the upper left window shows the vertical weighting functions for 18 spectral channels of the GOES sounder. The graphs in the lower left window show vertical profiles of pressure, temperature, water vapor and ozone. Users can re-draw these profiles, triggering recomputation of the weighting functions and data seen in the other windows. Any number of users may bring up this same user interface and collaborate in experimenting with the vertical profiles and weighting functions.