After start, a small icon near the clock is shown. The tooltip of this icon shows the username, computername and workgroup/domain. Further, for every network adapter,
all ip, gateway and dns server addresses are shown.
After a doubleclick on the icon, all this information is shown in a much nicer dialog. See screenshot below.
Alternatively you can start Nassau.exe /s
to just show the dialog immediately without the taskbar icon. Nassau.exe /e report.txt
will create a text file with all information.