Of all the hundreds of tags you can see in our mashup tag cloud, the second most popular behind "mapping" is "photo". How popular? As of now there are over 200 photo-related mashups listed at ProgammableWeb -- 202 by today's count.
Photo editing service Aviary has added a new HTTP-based API that allows developers to pass photos through filters, effects and even basic editing operations. Aviary "soft-launched" the new Aviary Effects API last week at SXSW, when we interviewed Aviary's Michael Galpert (video below). The new service could be used to create photo-sharing services like Instagram, CMS plugins to aid workflow or within social applications to create a standard look to all avatars.
Gravatar is an attempt to allow users to have one globally recognized avatar. The service, around for several years, allows a user can set an image as an avatar and have it recognized on a variety of sites. Later, users can change an avatar once and have it change on every Gravatar-enabled site that they use. Though the service is somewhat well known, what is not is its robust API for developers to integrate the Gravatar service into their own sites.