Magickly aims to make image manipulation possible as a simple web service. The Magickly API is very easy to use, and completely open source. It requires no API key, and allows a developer to use a lot of different image manipulations on any web-accessible image. Magickly is an open source, simplified version of the Aviary Effects API, which has a contest ending next week.
Swellcast combines all weather data needed to forecast surf conditions for surfers around Australia, and consolidates the data into a user friendly interface that takes the complexity out of understanding when and where the next big wave will appear. Swellcast also offers the forecast data and surf conditions through the Swellcast API.