Simple and easy to use program that helps configuring the network interfaces, allows to have multiple configurations for the same computer and to easy configure NAT for internet sharing.
Network Configuration Store is a free, open source application for network administrators, designed to automatically backup, revision and audit the configuration from Cisco IOS-based routers and switches.
VeriNeC (Verified Network Configuration) is a network configuration management application. It allows to import configuration, simulate and verify the network and distribute configuration to devices.