This week, domain name broker Sedo sold the highly-desirable domain name pizza.com for the cool sum of $2.6 million. And while that's an impressive amount of money to pay for something that doesn't actually exist, it still doesn't quite crack the top ten list of most expensive domain names ever sold.

Here's the list as it stands today. Naturally, this list only reflects domains that have actually been resold. Domains like yahoo.com which are still in use by the original owner don't count, and they may indeed be far more valuable if they were ever to hit the market.

The Ten Most Expensive Domain Names Ever Sold

1. Sex.com, $12.5 million
2. Porn.com, $9.5 million
3. Diamond.com, $7.5 million
4. Business.com, $7.5 million
5. Casino.com, $5.5 million
6. Asseenontv.com, $5 million
7. Korea.com, $5 million
8. Wine.com, $3.3 million
9. Creditcheck.com, $3 million
10. Vodka.com, $3 million

Some obvious ones there (sex and porn are worth money, eh?), and some surprises: Asseenontv? Creditcheck? The conventional wisdom holds that single-word domains are the most valuable domains, but exceptions abound.

I spoke to Sedo COO Jeremiah Johnston and he noted that there are a dozen variables that go into the value of a domain name, including length, memorability, and the competitive landscape for similar domains. (I wonder what Diamonds.com is worth.) He also thinks the market for domains will continue to go up, but of course, that's his job. Got a million-dollar domain you're sitting on? Maybe the time is right to look for a buyer.