Google Earth can display geographic data with a time component, and thus show animated maps. Animated mapping has garnered much attention among cartographers in the last decade.
I created a few Google Earth animated choropleth (literally, area-filling) maps of population change in Ohio. One map shows total population by county from 1900 to 2006. The other shows percent population change from decade to decade. Details on how I created these animated maps along with links to the downloadable KMZ files are below.
Making Maps: DIY Cartography 