The code and databases would have to reside on the server (simple data transfers). You would need at least one domain name, and you could use ports for the rest (example.com:80, example.com:81, etc.). Also, .info domain names are usually really cheap (at least through GoDaddy) and are commonly "throw away" names.
Nancy Injustice anywhere is a threat to justice everywhere. -- Dr. Martin L. King, Jr.
From: EPA WC
Thanks all for your help. I was able to get site1.dev and site2.dev going locally with my single drupal installation. But I have a new question. Let's say I want to share my new site1.dev and site2.dev in progress with someone on the Internet, how can this person get access to them with my server's ip address? Is this possible? If not, how can I do it? Again, I don't have actual domain names set up yet.