Geodesy & Navigation
A few examples of what you can ask Wolfram|Alpha about:
Latitude & Longitude
locate a point on Earth using latitude-longitude coordinates
find the coordinates of a city
compute the great-circle distance between points on the globe
compute the distance between cities
compute distances between multiple cities
compute the distance to the horizon
compute horizon distance for radio waves
get information about a compass heading
Geodetic Data
get information about a geodetic reference ellipsoid
compare multiple ellipsoids
get information about a geodetic datum
compare multiple geodetic data
compute current local gravitational field strength
compute gravitational field strength at specified coordinates
compute current local geomagnetic field strength
compute geomagnetic field strength for a given date and location