Public APIs : A collective list of free APIs for use in web development.
OpenCalais : Calais is a rapidly growing toolkit of capabilities that allow you to readily incorporate state-of-the-art semantic functionality within your blog, co...
Pipes : Pipes is a powerful composition tool to aggregate, manipulate, and mashup content from around the web.
Mapstraction : A javascript library to hide differences between mapping APIs.
API Security Checklist : Checklist of the most important security countermeasures when designing, testing, and releasing your API.
Bluepine is a DSL for defining API Schema/Endpoint with the capabilities to generate Open API (v3) spec, validate API request and serialize object for API response based on single schema definition.