The Behance Python SDK by aravenel allows API communication to create an interface for artists' portfolios. Although the SDK is a work in progress, author aravenel includes API object usage. The functionality section allows developers to search for projects, obtain user appreciation, and access collection projects.
Kooaba offers image recognition through its Kooaba API, allowing you to compile metadata on objects in your photos. This can be used for product recognition and pricing, but could also be used to augment personal photo collections, which can be so large that they are nearly impossible to search by hand. There are tons of use cases for image recognition and this API should really open up the field and bring more applications to market.
We all know we can search web pages for text, but many services are looking to go above and beyond with features like location and face tagging. The big downside to these features is that they rely on end users have to manually enter in the appropriate data. Really, when was the last time you tagged all the people in the 200 photos you just uploaded to Facebook? To help automate the process of face recognition, face.com have just opened their API.