FasterFox for FireFox 3.6
FasterFox is updated to now work for Firefox 3.6 but is still considered an experimental plug-in. I recommend FasterFox if you use Firefox.
make firefox faster
Improve Browsing Speed With OpenDNS
OpenDNS provides free IP addresses you can use instead of your local ISP DNS servers. This can improve your web browsing speeds by having faster DNS lookup.