One of the custom tasks shown during the Developer Summit plenary was authored by John Grayson, a veteran of ESRI's Applications Prototype Laboratory. Here's his description of the task.

This ArcGIS Explorer task has been implemented to visualize data collected by the AIRS satellite, a project of NASA's Jet Propulsion Laboratory.  The AIRS site provides the following description of the technology:

The Atmospheric Infrared Sounder (AIRS) looks down at the Earth and measures the infrared brightness coming up through and from the atmosphere. The AIRS optical system splits infrared radiation into its constituent "colors". The effect (but not the technique) is similar to rain drops splitting sunlight into a rainbow. The wavelengths used are sensitive to temperature and water vapor over a range of heights in the atmosphere, from the surface up into the stratosphere. The term "sounder" in the instrument's name refers to the fact that temperature and water vapor are measured as functions of height. AIRS also measures clouds, abundances of trace components in the atmosphere including ozone, carbon monoxide, carbon dioxide, methane, and sulfur dioxide, and detects suspended dust particles.

The data was preprocessed from its original HDF format into a geodatabase where information about when the data was collected and to which swath it pertained is maintained.  Additionally, curtain plots (vertical rasters) for each of the five attributes were generated as a server-side process.  The task starts out by reading the geodatabase and enabling the user to specify which date and swatch to visualize. The screen capture below shows the custom task interface, which allows the user to load the data and choose from different types of information to display. 

Footprints of each swath are drawn, and below they can be seen as blue rectangles on the globe. 

Using the custom task UI, the user can choose from a variety of types. The task uses OpenGL to load the curtain plots for the specified type, date, and swath onto the display.  Shown below is the complete set of curtain plots showing carbon monoxide levels for one of the swaths.

A slider control allows the user to quickly visualize one curtain plot at a time, providing a simple exploratory tool to visualize the data in the display.  Shown below is one of the curtain plots, and using the task slider the user can move forwards and backwards in the curtain plot sequence.

Here is another example, this one showing ozone levels. You can compare this to the earlier screen capture above in this post showing carbon monoxide levels.

The task leverages the ArcGIS Explorer SDK and it's support for integrating custom OpenGL implementations. The task makes use of exposed events that tell us when the application has finished drawing and when OpenGL calls can be made.  OpenGL allows the developer to create tasks that perform visualizations that are not otherwise possible via the Explorer API, and provides a wealth of potential possibilities for the Explorer developer.