Zx Sniffer is a freeware packet analyzer for Microsoft Windows used for network troubleshooting and analysis.
Zx Sniffer's main function is to passively collect packets sent across a computer network by putting the network card into promiscuous mode. It's also capable of decoding plaintext passwords from packets, unlike the low-level packet analyzer tcpdump. Later releases included a basic packet capture utility making it also a protocol analyzer, such as Wireshark.
Zx Sniffer is no longer maintained and its website is currently down.
Read more about Zx Sniffer: Features