GLPI - GLPI is the Information Resource-Manager with an additional Administration- Interface.
Total Network Inventory - Total Network Inventory is a piece of software designed to help with managing software inventory and auditing PC systems.
Lansweeper - Lansweeper discovers Windows, Linux and Mac machines in your network.
FusionInventory - Fork of the OCS Inventory project that enables users to inventory their IT assets.
Spiceworks Help Desk - Help desk software features that work for IT
NetBox - NetBox is an open source web application designed to help manage and document computer networks. NetBox was developed specifically to address the needs of network and infrastructure engineers.