Free Networking Software

VNC
Open-source cross-platform remote control solution.
http://www.realvnc.com/

Tight VNC
TightVNC - An enhanced VNC version with many new features, improvements, optimizations and bugfixes.
http://www.tightvnc.com/

Sys Aid
SysAid Help Desk Software by Ilient.
http://www.ilient.com/

Angry Ziber
Angry IP Scanner is an open-source and cross-platform network scanner designed to be fast and simple to use. It scans IP addresses and ports as well as has many other features.
http://www.angryziber.com/w/Home

Avvenu Access And Share
Avvenu gives you remote access to your computer via your cell phone, PDA, or another computer. Avvenu Music lets you listen and share your music.
http://www.avvenu.com/

Port Detective
PortDetective sniffs out your Open Ports on your ISP and Local PC
http://www.portdetective.com/

Cost Aware
Network traffic measurement and bandwidth shaping software
http://www.costaware.net/

Cybercafe Surfshop
Dynasoft Ltd are the makers of Cybercafe SurfShop, a market-leading Internet & games cafe software, telecom billing software consultants
http://www.dynasoft.net/surfshop/

Team Viewer
TeamViewer establishes connections to any PC all around the world within just a few seconds. You can remote control your partner's PC as if you were sitting right in front of it.
http://www.teamviewer.com/

Wall Cooler VPN
Remote Access computers and Networks from anywhere. WallCooler VPN is a pure software SSL VPN: fast, secure and as powerfull as a hardware VPN solution. Remote Access at its best.
http://www.vedivi.com/

Ethereal
Ethereal is used by network professionals around the world for troubleshooting, analysis, software and protocol development, and education.
http://ethereal.0ni0n.org/

Angry Ip Scanner
Angry IP scanner is a very fast IP and port scanner.
http://download.chip.eu/en/Angry-IP-scanner-2.21_703533.html

Minute Timer
Minute Timer - This is a tiny count down timer program built completely in assembly language. - Review and free download at FileCart.com
http://www.filecart.com/details/26837/379/Minute_Timer.php

VPN Evolved
LogMeIn Hamachi is a VPN service that easily sets up in 10 minutes, and enables secure remote access to your business network, anywhere there's an Internet connection.
https://secure.logmein.com/products/hamachi/vpn.asp