The granddady of the domain name business is Verisign, which is the provider of all the .com and .net domain names. All of the registrars are simply reselling the domain names they acquire through Verisign. VRSN has a clean balance sheet with $500mm in net cash and trades also for just a little over ten times cash flows.

Google struck a deal in December 2006 with private company GoDaddy, who is the largest domain name registrar. Google is partnering with GoDaddy.com to add domain registration services to its Google Apps for Your Domain product. Google said in a statement that it plans to charge customers $10 per domain, per year. It's a price that includes private registration to protect personal information. GoDaddy is a veritable cash machine but pulled their S1 filing because they didn't like how GAAP forced them to defer, sometimes for years, cash revenues they already had in the bank. "There's no need for us to go public," CEO Bob Parsons said at the time.

Marchex was started by former Go2Net founder and CEO Russ Horowitz. They own over 200,000 domain names including the domains for every zip code in the country. Marchex trades for just a little over 10 times cash flows (enterprise value over EBITDA) and had year over year revenue growth of 26% last quarter.

TuCows, another AMEX-listed company, helps connect buyers and sellers of domain names and takes fees in the middle. TuCows is currently the fourth largest domain name registrar.

InterSearch Group (IGM) on the AMEX owns valuable domains like IRS.com.

Communicate.com (CMNN.ob) is a small public company that is also sitting on quite a few domain names, including importers.com, perfume.com, body.com, cricket.com, and others. The company has been generating revenue by selling domain names, but more recently, by actually setting up real e-commerce sites on some of these domains and making decent money from retail. For instance, Perfume.com has been having bustling sales.