For music fans who enjoy listening to playlists on their laptops or desktops, Tomahawk is a music player with a few extra bells and whistles that may be of some interest. It's an open-source, cross-platform music player, which means it enables a user to play music stored on their own hard drives as well as from a variety of other music sources like Spotify, SoundCloud, YouTube and more. The Toma.hk API makes this functionality available to developers or users to add songs to websites.
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.