Ping Meter Gadget - Customizable, graphical, semi-transparent ping (latency) meter.
Win10Pcap - Win10Pcap is a WinPcap-based Ethernet packet capture library.
NetTK - NetTK, Network Tool Kit, is an Open Source alternative for monitoring and troubleshooting your...
Npcap - Npcap is the Nmap Project's packet sniffing library for 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.
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.