World Airport Explorer - From the creators of GeoWalk comes this awesome world airport explorer. Available in English, German and English it displays all primary and secondary airports for all countries around the world. To get started click here and choose your language from the flag key at the top right. Drill down from continent, area, country then region to view all airports. Primary airports are marked with an airplane marker and smaller airports with colored pins. Each airport mashes up with Wikipedia entries (where available) and Flickr images tagged for that airport! Very cool.
It's worth mentioning that the above mashup is born out of another really cool Flickr + Wikipedia + Hotel info mashup for world locations. It's called GeoWalk and I've mentioned it before. Tap anywhere on the world map and it gives you pictures, information and hotel info for that very spot. Neat for preparing for travel or while you're on the road and want to learn more about your present location!
Google World Time Map - This is not a new Google Maps tool concept but the interface and method to learn the time is. Roll the mouse over the map and the info-window instantly displays the present time for that location. GChart is another good world time map concept with other data mashed up for you to explore on.