We recently came across this article which talks about a study that uses lightning monitoring to better predict the weather. The study used data from the University of Washington based World Wide Lightning Location Network (WWLLN), which gathers information about lightning strikes around the world using a network of ground based censors. The WWLLN website shows animated maps of recent lightning strikes, but also provides this KML file which shows 1 hour of global data ending 6 hours ago in Google Earth.
One thing I have personally noticed while living in Cape Town is how rare lightning is here compared to Zambia. This observation is borne out by this map that Frank put in Google Earth back in 2006 using a NASA created map.