In July 2010, the Internet got a little bigger when .CO domain extensions were made available to the public.

Today, Cambridge-based domain marketplace Sedo.com (which stands for “search engine for domain offers”), announced its upcoming auction for some of the most valuable .CO domains still available. These include Business.co, Art.co, Shoes.co, Technology.co, Advertising.co among many others.

With over 90 billion .com domains already claimed, it can be extremely frustrating finding a perfect, credible, and recognizable .com domain for a new company or product. The .CO domain is poised to become the next premier web address, and includes ‘leading-edge technology, enhanced security, and unprecedented rights protections for brand owners.’

.CO Internet is the Registry Operator for the .CO domain, and has a breadth of information on their website, including a full list of registries who are offering the .CO domains like GoDaddy, Network Solutions, and Register.com. From their website:

“Associated globally with the words “COmpany,” “COrporation” and “COmmerce” – the .CO domain is easy to recognize, simple to remember and flexible to use. And that makes it the perfect platform for today’s socially networked individuals, entrepreneurs and companies to create .COmmunities, share .COntent, and .COnnect, .COmmunicate and .COllaborate.”

Companies with current .com domains are also interested in .CO domains for reasons varying from branding to security. Twitter (T.co), Overstock (O.co), and Politico (Politi.co) quickly swiped up their preferred domains back in July. Twitter is using it as part of a service to “protect users from harmful activity,” Overstock – who reportedly paid $350,000 for O.co – is using it for branding as a redirect straight to Overstock.com, and Politico is using it for their short URLs when anyone shares a link from their site.

“Companies that want to expand their brand online and increase traffic should take a close look at the .CO names that could benefit their business. Now is the time for action,” said Jeremiah Johnston, Sedo’s COO and General Council. “Once these unique properties are claimed, it’s unlikely that they’ll be available again for some time.”

The Sedo.com auction will take place from February 10th through 17th. and you can learn more — including a full list of available domains — on their website.