PCFinder is an application that will scan an IP Address range that you input, and will retrieve the MAC Addresses and Host Names of the computers that are connected to your Local Area Network.
Features:

Adjustable Thread Count - Improves Performance
Sortable Results List
Multiple Scanning Options - Tweak for Better Speed or Results
Remove Unwanted Results
Options are Remembered Across Sessions
Export Results to Multiple Formats
Text (Tab Delimited)
Excel (CSV - Comma Sepearted Values)
Web Page (HTML - Hyper Text Markup Language)
Possible Uses:

Scan computers to determine if there is an unauthorized device on your network.
Use to create a list of MAC Addresses to allow for Wireless Access.
Confirm that your networks Computer Name Scheme has been followed.
Determine if a PC is powered on or not.
Locate a PC´s IP Address by it´s name or it´s MAC Address.