Streamzoo, an alternative to Instagram, has just released the Streamzoo API. According to the documentation, the API uses HTTP calls and returns JSON. It joins 341 photo APIs in the ProgrammableWeb directory.
Animetrics, a leading developer of 2D to 3D face recognition and face creation solutions, provides the Animetrics Face Recognition that can be used to detect human faces in pictures and match them against a set of known or documented faces. This tool is specifically useful for applications for the fashion and online entertainment industries, or for law enforcement or military intelligence where accurate identity resolution is a necessity.
You've spent years sharing your life on Facebook, Twitter, Foursquare, and recently adding photos to the mix with Instagram. If you're like me and many others, sharing this stuff also serves as a means of archiving things to be able to easily look back later and say, "remember that? That was great."