That’s the beauty of this program being open source.
Here’s what you do:
In the URL bar, type “about:config” and press enter. This will bring up the configuration “menu” where you can change the parameters of Firefox.

Note that these are what I’ve found to REALLY speed up my Firefox significantly – and these settings seem to be common among everybody else as well. But these settings are optimized for broadband connections – I mean with as much concurrent requests we’re going to open up with pipelining… lol… you’d better have a big connection.

Double Click on the following settins and put in the numbers below – for the true / false booleans – they’ll change when you double click.

Code:
browser.tabs.showSingleWindowModePrefs – true
network.http.max-connections – 48
network.http.max-connections-per-server – 16
network.http.max-persistent-connections-per-proxy – 8
network.http.max-persistent-connections-per-server – 4
network.http.pipelining – true
network.http.pipelining.maxrequests – 100
network.http.proxy.pipelining – true
network.http.request.timeout – 300

One more thing… Right-click somewhere on that screen and add a NEW -> Integer. Name it “nglayout.initialpaint.delay” and set its value to “0″. This value is the amount of time the browser waits before it acts on information it receives. Since you’re broadband – it shouldn’t have to wait.

Now you should notice you’re loading pages MUCH faster now!