- Wayfaring API: This useful service allows you to easily build personalized maps on top of Google Maps. Their brand new REST API provides a way to automate map creation. Data can be returned in JSON format and API wrappers for Ruby and PHP are provided.
- 30 Boxes API: The 30 Boxes calendaring service has an Ajax-rich UI and some real buzz. The REST-based API allows you to access User and Event data. The API, like the service itself, is in early beta.
- ISBNdb API: The ISBNdb.com project is a database of books in different languages providing on-line and remote research tools for individuals, librarians, scientists, etc. This API gets you access to data on 1,800,000 books; almost 3,000,000 library records, 750,000 authors, and more than 10,000,000 records of actual and historic prices, as well as other data.
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