NetworkActiv Port Scanner
NetworkActiv Port Scanner is a network exploration and administration tool that allows you to scan and explore internal LANs and external WANs. Because of the versatility and choosable operating modes available in NetworkActiv Port Scanner, it may be used by experienced network administrators as... NetworkActiv Port Scanner provides scanning performance simply not found in other Windows based network scanners, but one will need to actually try it to understand just how fast a network scan can be.
http://www.networkactiv.com/NetworkActivPortScannerV4.0.exe - 2Mb - Download - Screenshot

NetworkActiv PIAFCTM (Free Edition)
As seen on TechTV, NetworkActiv Packet Intercepting, Analyzing, File Constructing Traffic Monitor (PIAFCTM) provides not only what you would expect in a good packet analyzer, but also provides HTTP (Web page) file capturing by watching the packets of transferred Web page files and piecing them... 100% freeware and 100% free from ads, spyware, and nags. ... Has a very easy to use, Windows based graphical user interface so that you can get started without reading a book.
http://www.networkactiv.com/NetworkActivPIAFCTMv1.5.exe - 304Kb - Download - Screenshot

NetworkActiv PIAFCTM
Easy yet advanced, quad-mode packet analyzer, Mode 1 (Packet Interceptor) While in this mode, PIAFCTM captures and analyzes network data packets. PIAFCTM allows you to view special information encoded in each packet such as the source and destination IP addresses, the source and destination... When capturing using the NetworkActiv PIAFCTM Packet Driver, data is captured at the ethernet level allowing you to see the MAC (Media Access Control) addresses of each computer from which you have received packets.
http://www.networkactiv.com/NetworkActivPIAFCTMv2.2.exe - 2Mb - Download - Screenshot

NetworkActiv AUTAPF
Configurable UDP and TCP port forwarding. With TCP port forwarding you can hide your web-server behind a gateway computer for added security. With UDP port forwarding you can run a multiplayer game server behind a gateway computer for added security and versatility. ... Can be set up to hide in taskbar. ... Can be run without installing (if desired). ... Can be set up to bounce connections back to connector (on same or different port). ... Notice: This is 100% freeware; No ads, banners, spyware, or nags.
http://www.networkactiv.com/NetworkActivAUTAPFv1.0.exe - 168Kb - Download - Screenshot

NetworkActiv Web Server
Very easy to use, intuitive, 100% freeware, secure, Windows based web server (HTTP Daemon) with a multilingual graphical user interface and a real-time on-screen connection log. Has a small footprint of just 608KB (not compressed! ) and can be easily configured in just a few minutes. ... Restrictable access by password protection and by IP address range allowing/blocking. ... Supports Common Log Format and Extended Common Log Format. ... Can be run as a service on NT based systems. ... This server can even be run without installing.
http://www.networkactiv.com/NetworkActivWebServerV3.5.exe - 612Kb - Download - Screenshot