To do some tracing of WCF messages I was planning to use Ethereal, a network sniffing tool. I used this tool successfully a couple of years ago. While searching for the download, I discovered it’s now known under the name ‘Wireshark’: http://www.wireshark.org/
More details on the name change can be found here: http://www.wireshark.org/faq.html#q1.2
