Excellent port/subnet scanner with 3 levels of verbosity and strobe scan options. Under 300 lines of code, fast, accurate, optional GTK interface.
You can download it from the following link: https://packetstormsecurity.com/files/download/14109/PortScanner-1.2.tar.gz
Source: https://packetstormsecurity.com/files/14109/PortScanner-1.2.tar.gz.html