Internet Connectivity Monitor - This a lightweight program that provides you with a way to monitor your internet connection uptime.
Ping Meter Gadget - Customizable, graphical, semi-transparent ping (latency) meter.
PuTTY - Popular free terminal application. Mostly used as an SSH client.
SmokePing - Smokeping is a tool for measuring latency.
Open Nettest - Open Nettest is a platform for collecting, processing and visualizing data related QoS and QoE.
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.