Total Network Inventory: Professional PC audit and network inventory management software - fits best for a for companies of all sizes. Free for 60 days.
FinancialForce HCM - FinancialForce.com provides cloud back-office applications for Salesforce CRM.
Network Inventory Advisor - Network Inventory Advisor audits all network software and hardware simply and efficiently
Vibe HCM - Vibe HCM is a recruiting and employee engagement platform.
Lansweeper - Lansweeper discovers Windows, Linux and Mac machines in your network.
BMC Remedy - IT Service Management Suite
Nmap - Nmap Free Security Scanner, Port Scanner, & Network Exploration Tool. Download open source software for Linux, Windows, UNIX, FreeBSD, etc.