Redis - Redis is an open source in-memory data structure project implementing a distributed, in-memory key-value database with optional durability.
Binders by Generism - High Level Database & Forms Application. An innovative solution to manage your database.
MongoDB - MongoDB (from "humongous") is a scalable, high-performance NoSQL database.
ArangoDB - A distributed open-source database with a flexible data model for documents, graphs, and key-values.
memcached - High-performance, distributed memory object caching system
Aibase - Creative Data Manager