Basecamp offers project management tools to collaborate and communicate. The Basecamp PHP library created by Netvlies contains authorization with OAuth, API calls, and identification. It aims to facilitate project management with assigned projects, to-do lists, and active projects.
Online diagramming service Creately opened its Creately API to the public this month, and with some surprisingly innovative features. While providing obvious features to make its service available to outside developers, and several "above and beyond" features, such as easy embedding of diagrams, Creately has done something fairly unique: open up its own, web-based file format for other developers to use.