Speed up Firefox

If you only try one of these tips, try pipelining - either way, you will notice these changes.

Here's the source. (Works on FF, Mozilla, Camino, etc.)
Don't be lazy.

Enable Pipelining

Pipelining is an experimental feature, designed to improve page-load
performance, that is unfortunately not well supported by some web servers
and proxies. To try it out, by using about:config
to set the following preferences:

network.http.pipelining

Set this to true, to enable pipelining.

network.http.proxy.pipelining

Set this to true, to enable pipelining to the proxy server.

network.http.pipelining.maxrequests

Set this to 8, to have a maximum of 8 pipelining requests at once. Possible values are from 1 to 8.

Speed up page rendering

By default, Firefox doesn't try to render a web page for 250
milliseconds while it's waiting for data. If you use about:config
to add the Integer preference nglayout.initialpaint.delay, and
set the value to 0, Firefox immediately starts to display the
page, even without complete data. The drawback, especially on slower
machines, is that the total time to display the page will be longer.