1. MongoDB (from "humongous") is a scalable, high-performance, open source NoSQL database.

    open-source

  2. Redis is an open source in-memory data structure project implementing a distributed, in-memory key-value database with optional durability.

  3. A distributed open-source database with a flexible data model for documents, graphs, and key-values.

  4. HTTP + JSON document database with Map Reduce views and peer-based replication

  5. PostgreSQL is a powerful, open source object-relational database system.

  6. The open-source database for the realtime web

  7. Manage a massive range of data fast and without losing.

  8. Microsoft Azure is an open, flexible, enterprise-grade cloud computing platform. Move faster, do more, and save money with IaaS + PaaS. Try for FREE.

  9. Document-Oriented NoSQL Database

  10. An enhanced, drop-in replacement for MySQL

  11. OrientDB - The World's First Distributed Multi-Model NoSQL Database with a Graph Database Engine.

  12. SQLite Home Page