NASA has just released CAPS, which is short for Communication Alert and Prediction System. This system enables that anyone can get a model of the Earth’s Ionosphere live.
April 30, 2008: Today, NASA-funded researchers released
How to Launch the 4D Ionosphere
"One, download and install Google Earth."
"Two, visit our web site and click on the link 'Total Electron Content.'"
via: CAPS: A '4D' Model of our Ionosphere - Instablogs
NASA - Explore the Ionosphere (from the safety of your own home)
NASA - How to Launch the 4D Ionosphere
CAPS - Communication Alert Planning System