The Google Distance Matrix Go Library by Jon Dunning affords to get the distance and travel times between various origins and destinations. It handles Google API rate limiting and URL length. Available installation, usage, and limitations. Supports driving, walking, and bicycling modes.
There are any number of questions that can be answered by Wikipedia, but you can add "where am I?" to the list. Given any latitude/longitude coordinates, the WikiLocation API will find you corresponding Wikipedia articles to tell you about your surroundings.
Earlier this week Microsoft announced that it is making some of the imagery used in its Virtual Earth platform available for purchase (more on Virtual Earth in our VE SDK profile). The imagery, taken with Microsoft's proprietary UltraCam shown below is available for approximately 200 cities (in high resolution and averaging less than two years old).
If you're looking for a traffic data web service, you probably have not been able to find one for free. Now mapping pioneer MapQuest is beta testing a service it says provides "real time traffic information related to incidents, markets and flow."