As a UNIX and network guy, I try to optimize systems and networks to deliver the most bang for the buck. I recently came across the following post on the Mozilla Zine web forums:
http://forums.mozillazine.org/viewtopic.php?t=53650
This link covers several tunables for Firefox, several of which can significantly speedup page load times (especially when you have a tabbed list of news sites):
network.http.max-connections: This value controls the maximum number of outbound TCP connections. network.http.max-connections accepts an integer value and defaults to 24.
network.http.max-connections-per-server: This value controls the number of concurrent requests to a single site. For sites that contains hundreds of URIs in a single page, this should speedup page load times (barring the remote site isn’t rate limiting inbound connections). network.http.max-connections-per-server accepts an integer value and defaults to 8.
network.http.max-persistent-connections-per-server && network.http.max-persistent-connections-per-proxy: These values control the number of persistent HTTP connections that can be maintainted to a website. Both parameters accept integer values and default to 2 and 4.
network.http.pipelining && network.http.proxy.pipelining: These values control the HTTP 1.1 pipelining feature, which allows multiple HTTP requests to be requested at connection setup. Both parameters accept boolean “true”/“false” values and default to “false.”
You can tweak these settings by typing “about:config” into the Firefox navigation toolbar, or by directly editing the user.js preferences file. I picked my current values by adjusting the current values, clearing the cache, and calculating the time it took Firefox to load 50 tabs. I was able to cut 14 seconds off my news site load time by doubling, and sometimes tripling the default values :)