Over at the Google Earth Community there is a forum called Dynamic Data Layers. The idea is to create Google Earth layers based on data that is constantly updated. Examples include such things as weather data and crime statistics, but any type of data that is dynamic in nature could be used. (I'm holding out for school attendance data... :-) )
This morning I followed a link from Frank Taylor's Google Earth Blog to Andrew Browns' post about Aurora (Northern Lights) Activity Plots. He came up with the idea to talk to NOAA about making aurora activity data available from the POES satellite in a format that could be presented dynamically in Google Earth. The data is not a photograph, but a graphical representation of aurora activity over points on the Earth. While NOAA makes this information available in a graphic form on their web site, the same data in Google Earth is much more compelling.