Not sure if this is the best forum for this question:
Normally, if we use apache, http://localhost is the only URL we can use, and that means only 1 site (equivalent of 1 domain). Now, I use it for development purposes only so I don't really care about how you do it, as long as it doesn't involve the Internet when running apache (I use a modem). What I want is something like: http://site1.localhost/, http://site2.localhost/ etc.
# VirtualHost: Allows the daemon to respond to requests for more than one
# server address, if your server machine is configured to accept IP packets
# for multiple addresses. This can be accomplished with the ifconfig
# alias flag, or through kernel patches like VIF.
# Any httpd.conf or srm.conf directive may go into a VirtualHost command.
# See also the BindAddress entry.