I use firebug to trace the HTTP requests, mainly. I know there are alternatives (for both Chrome and Firefox), but none of them compare to firebug. May be its because of my comfort/acquaintance level with firebug.

Used to think like you, but chrome's network tab (in the developer tools) has really come a long way

You are probably correct. But you know, dev. tools are like IDEs/Editors. Once you get settled with one, there is a level of comfort with the tool, you dont get with others.

if were going to talk about HTTP monitor alternatives please dont forget to talk about Charles. In many ways i prefer it to built in browser monitors because it is designed to capture any requests regardless of source.