Angry IP Scanner
A free and open source IP address and port scanner.
Trouble finding a nearby IP address? Don’t get mad; get Angry. Angry IP Scanner can locate IP addresses and ports within multiple ranges to see which ones are active. And with additional plugins, additional information about each IP address can be gathered. Other features include the ability to gather NetBIOS information (computer name, workgroup name, and currently logged in Windows user), favorite IP address ranges, web server detection, and customizable openers. Scanned results can be saved to CSV, TXT, XML, or IP-Port list file format.
