Open Library has a RESTful API, best used to link into Open Library data in JSON, YAML and RDF/XML.
Programming Quotes API for open source projects.
Samsara provides API endpoints for interacting with Samsara Cloud, so that you can build powerful applications and custom solutions with sensor data. Samsara has endpoints available to track and analyze sensors, vehicles, and entire fleets.
The Artsy Public API provides access to images of historic artwork and related information on artsy.net for educational and other non-commercial purposes.
Descriptions of all nouns (names, places, animals, things) from vedic literature
Gods and poets, their categories, and the verse meters, with the mandal and sukta number
Global Search Engine
A database of ways mobile vendors inhibit apps background activity
Search all podcasts and episodes on the Internet
This is a community with the aim of collecting as many internet radio stations as possible.