XArp - XArp – Advanced ARP Spoofing Detection XArp performs advanced ARP spoofing detection mechanisms – made to secure your network.
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..
Paessler PRTG - An advanced network monitoring solution to monitor network up/downtime, traffic and usage.
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.
NetCut - NetCut is a Software that helps you admin your network by purely on ARP protocol.
Ping Meter Gadget - Customizable, graphical, semi-transparent ping (latency) meter.