In my never ending quest to find the best tool to debug ajax applications, I came across a lot of cool extensions that you can add to Firefox to make it more ajax-debug-a-rific.
Finally, there is a tool called TamperData which lets you track and modify HTTP requests. Basically you can change the data that is sent to the webserver on the fly. It's kinda akin to an HTTP Proxy that some individuals use to probe for vulnerabilities in web software.
Here are the links for the three I just mentioned.
One other thing, I added a link to my blog roll. My friend Ryan from school recently pointed me to his blog. Check it out.
This little area is just a listing of the current tabs I have opened in Firefox that have piqued my interest. They may interest you too though.