Network Auditor
Download Sites:
Network Auditor allows you to scan the machines on your network, to determine what hardware and software is installed on these machines, and then to add these machines to a database.
This database constitutes your Network Inventory.
Network Auditor can also compare the hardware and software that it finds on machines against what you have recorded in your inventory and alert you of changes (for example, if a piece of hardware stops working or if new software is installed on a machine).
by Avery Hilditch on Jan 29, 2003 
I run the helpdesk on a project with over 250 PCs so I was interested in a program that would do what this one claims.
Unfortunately, I could not even get the program to install. I didn't even get as far as the initial Intro dialog on the install. Instead I got a dialog telling me I could abort or retry but didn't tell me whatI could abort or retry. I saw it had a 5 stars on another site. I wouldn't even give it 1 if 0 were available.
A similar, cheaper, product called the Software Asset Controller did all that I wanted of it. Installation was breeze and it works like a dream - fast and efficient. Go to http://www.pcprofile.com to try it out.
Network Auditor keywords: monitor, audit, network, inventory, helpdesk, help desk, faults, detect, detection, auditor, network audit