Just found a huge time-saver for working with localhost sites which require you to use the build in web server on Visual Studio
(Cassini). If you look at the Net firebug window you will notice that the bottleneck is the DNS lookup which can be several seconds.
This is due to the IPv6 DNS problem within firefox and can be fixed by setting the network.dns.disableIPv6 setting to true within the about:config
and the page loads up almost instantly: