Internet, give me my movie details
When you browse your home video library you would like to see something more (like on the picture below) than just a plain list of movies titles. It's good to see the poster, plot, credits, ratings exactly those details that have on IMDB, Rotten Tomatoes or polish FilmWeb... so how to get it?
So before you roll up your sleeves and start assembling own web crawler that rips off the data... take advantage of http://www.programmableweb.com/ and check if between nearly 15k API listed there is something that satisfies you.
The Movie Database API
ProgramableWeb allows me to filter up TMDb API - as I believe most featured and free movie data API. TMDB Api is present on scene since 2009 and it currently data feed foundation for tens of: applications, media players, media centers (including XBMC), across different platforms.
TMDb API supports JSON and JSONP response formats (XML and YAML has been officailly dropped). Requests rate is limited to 40 request per 10 seconds for single IP address. SSL connection is also supported. TMDb API allows you to hit the data in two different modes - logged in with private account or as a guest. What is important, logging with private account is mandatory only when you want to contribute some data back to TMDb (rate movies is not included into the restrictions).
Before you decide to handle raw API by your own you can take a look into wrappers and libraries section. TMDb lists wrappers written in most popular languages, contributed by community - there are four(!) of them for C# only.
TMDb is well documented on apiary - that is API Design Stack that allow design, prototype, document and test APIs.
Apiary besides of nice and clear UX contains one feature called Console that allows you easily examine API documentation without effort and other JSON tools involved. Sent tab, allows you to validate any referenced requests against API (TMDb provides Mock Server, Debugging Proxy and Production end points) and fetch the response. Another cool-thing can be found in code example tab that provides code snippets for different languages.