If you've been doing any form of Ajax development, you know how invaluable an HTTP sniffer & DOM inspector is. And quite honestly, I've found none better than the FireBug extension in FireFox to handle these tasks. Its a nice little plugin that sits unobtrusively until you need it.
Well, Joe Hewitt, the author of FireBug, has released an open beta of the anxiously awaited FireBug 1.0. This is a MAJOR revamp of the original version and a must download if you're doing any type of Ajax, CSS or DOM manipulation. Trust me when I tell you that this plugin is invaluable and you will end up using it all of the time.