Network Lights - Network Lights is a Windows program, which blinks keyboard LEDs (Light Emitting Diode) indicating outgoing and incoming network packets on network interface.
Multiping - Get MultiPing Support. Network monitoring in 60 seconds. MultiPing provides a graphical view of network performance, monitors hundreds of targets, and sends automatic alerts..
FreeMeter - Monitor network bandwidth (C#.NET 2k/XP+). Desktop and Systray graph.
SmokePing - Smokeping is a tool for measuring latency.
TrafficMonitor - TrafficMonitor is a network monitoring suspension window software in Windows.
Fping (open source) - fping is a program to send ICMP echo probes to network hosts, similar to ping, but much better performing when pinging multiple hosts.