Firebug for Firefox a scale down tool

I haven't tried Firebug. As an alternative for HttpWatch, "Live HTTP Headers" seems popular. My favorite is "Tamper Data" (I don't actually use it for tampering, simply for it's presentation of the data). Tamper Data has a mode to generate Gantt charts at least vaguely similar to Firebug.

 

 

IBM Page Detailer seems to still be available for download, too, if the charting stuff is all you're after.

 

 

On the general topic of measuring web page performance using FireFox, I suggest checking out iMacros (in particular the "Stopwatch" example), or for less formal performance measurement, Fasterfox includes a page load timer in the status bar which I've found to be handy.

 

 

Last but not least, if you find a customer that wants to keep a close eye on their performance in a more formal way, services like Gomez or Keynote can definitely generate some pretty reports. :) They also have 'on demand' modes where you just type in a URL for one-off testing (if you have an account with them...).