NetworkSpy 1.6 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This software is compatible with Mac OS X 10.6 or later. This Mac application was originally designed by Sparkfield Software. The most popular versions among NetworkSpy for Mac users are 1.6, 1.5 and 1.2. The software is included in Internet & Network Tools. We recommend checking the downloaded files with any free antivirus.
From the developer:
NetworkSpy is a Mac OS X application that can display all the active network connections on your computer along with the corresponding applications which are accessing the network. The dock icon also shows all the connected applications.
To find out information about a specific connection (such as hostname, port, protocol and geographical location), click on the ip address in the connection table.
You may want to check out more Mac applications, such as LaCie Ethernet Agent, Covenant Eyes or AirGrab Network Packet Analyzer, which might be related to NetworkSpy.