MongoDB - MongoDB (from "humongous") is a scalable, high-performance, open source NoSQL database.
BIND - BIND is by far the most widely used DNS software on the Internet.
PostgreSQL - PostgreSQL is a powerful, open source object-relational database system.
PowerDNS - PowerDNS offers open source DNS software, services, and support.
RRDTool - High performance data logging and graphing system for time series data
Simple DNS Plus - DNS Server for Windows