I wrote a recent post about managing ALL of your content where I discuss the idea that your content is not just the content on your site.

In my continuing research for better ways to manage content I came across a real gem. Net::DNS which is a helpful tool for resolving DNS and gives you a different perspective than Ruby's Resolv.

If you want to check if a domain is valid then something as simple as this might do the trick:

Net::DNS::Resolver.start("google.com").answer.size > 0

But of course, there's much more to it than that. Check it out!