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.
NetLimiter - NetLimiter is an ultimate Internet traffic control and monitoring tool designed for Windows.
OpenSpeedTest - Broadband Internet Speed Test Unlocked!
NetBalancer - NetBalancer is a Windows application for local network traffic control and monitoring.
Ping Meter Gadget - Customizable, graphical, semi-transparent ping (latency) meter.
Bandwidth Manager - Bandwidth management, bandwidth limiting and traffic shaping software for Windows