Exversion is hoping the need to access wide-ranging open datasets has matured enough to create a viable business as an open data marketplace. Their new Exversion API provides developers with a RESTful interface to search and access the open datasets stored on the Exversion data platform. At present, the API returns queries in JSON or XML format, with full XML support to be provided in the near future.
The YouTube API is one of the most popular APIs in the directory, where we currently list over 500 YouTube mashups. Some recent mashups of the day have really stretched the definition of a YouTube mashup. These three examples below would surely be in the running if we ever revisit our top 10 YouTube mashups of all time.