York is the perfect freeware to keep an eye on what's going on in your network.
You can choose a client on your network and follow his clicks or log all source, destination [fqdn or IP address], and packet size of all network traffic on your network. Just for kicks York will show you a slideshow of all the pictures embedded in the HTML of sites visited on your network.
Log source, destination [fqdn or IP address], and packet size of all network traffic on your network, of course also outbound traffic. The network card will be set into promiscuous mode.
Save sniffed HTTP and FTP files. Just for fun, pictures are shown in a slideshow and a screensaver-like window
Sniff for HTTP, FTP, POP3, SMTP, SMB, VNC, and AIM password/hash and HTTP cookies like 'GX'
Select a client and follow his clicks in your browser. [WebSession]
Screensaver included. It shows sniffed pictures in a slideshow
For the advanced user: You can capture traffic into a pcap file, send a pcap file and replay a pcap file
For advanced users: You can restrict captured traffic by tcpdump filters
Please note, WinPcap [www.winpcap.org] is used to get the network traffic. The Setup will install WinPcap automatically
The columns in the log file are tabulator separated for easy import into Excel