PingInfoView - PingInfoView is a small utility that allows you to easily ping multiple host names and IP addresses, and watch the result in one table.
Scapy - Scapy is a powerful interactive packet manipulation program.
SmokePing - Smokeping is a tool for measuring latency.
Nipper - Nipper - Neat Internet Protocol Packet EditoR - is a graphical packet generation tool.
PingPlotter - PingPlotter is a troubleshooting tool that helps IT professionals and neophytes identify, diagnose, and resolve network issues.
Packet Editor - Packet Editor a free packet editing tool to debug winsock based network solutions.