Monitoring HTTP requests

One of the tools I use the most is TCPMON. Basically it acts as a proxy or sender for HTTP requests, but it lets you see them. Mainly I use it for SOAP, but it works for any HTTP traffic.
Now the Axis2/C and WSF/C projects have done a command-line version in C. Kau has blogged about it here. The benefit of this one is that (a) you don't need a JVM, and (b) its more like a Unix toolkit... it sits and logs to file. I won't be giving up on the Graphical version, but this is an extra tool in my toolbox.