Perhaps that Bing-Yahoo search deal is paying off. Even though Maps and Flickr aren't known to be part of the deal, Microsoft has connected its Bing Maps to the Flickr API in a unique way. It overlays geotagged Creative Commons photos over its current StreetSide imagery, as shown in the video embedded below.
Mashup games are always fun. Those built upon FourSquare have an extra layer of enjoyment, because they're tied to the real world. In the case of City Warfare, players use various water weaponry to soak other FourSquare users.
Swellcast combines all weather data needed to forecast surf conditions for surfers around Australia, and consolidates the data into a user friendly interface that takes the complexity out of understanding when and where the next big wave will appear. Swellcast also offers the forecast data and surf conditions through the Swellcast API.