Top 5 World's Tallest Skyscrapers - Wondering where the top 5 tallest buildings in the world are? Virtual Tourism has organized the collection of them with links to their satellite imagery on Google Maps. Keir Clarke has also handpicked some videos from YouTube so you can have a look at the structures themselves.
Round the World Cycle Tour - A Google Map of an around the world cycle tour. An accompanying blog post explains more about the map and be sure to use the "Area to Show on the Map" drop-down menu to switch over to other parts of the world. Looks like a great trip! :)
Google Maps CIA World Factbook Viewer - Stephansmap.org features the 2004 and 2005/6 CIA World Factbook using the stephansmap interface and Google Maps. This way to browse the contents of the World Factbook is much more accessible and easier to see how things work, covering both tags and time.