Those of you tired of seeing the same useless sites pop up in your Google search results can now stop those sites from appearing.

A new option launched yesterday by the search giant lets you hide specific domains that keep popping up in your search results, preventing them from showing up again.

Depending on the type of searches you run, you may now see a link called "Block all [name of site] results" next to the cached link for certain results. Click on the link, and Google will ask for confirmation on whether you really want to remove that site.

In a blog posted yesterday, Google explained that the links to block a site will appear even if you're not logged in with your Google account. But you will need to log in to confirm a blocked site.

The next time you search for results that would normally include the newly blocked site, you'll see a message telling you that those results have been blocked. You can access all of your blocked sites from your Google Search Settings page, allowing you to unblock a site or block new sites directly.

The option just started rolling out yesterday and continues today, so not everyone may see it yet. Blocking sites is supported in Chrome 9 or higher, Internet Explorer 8 or higher, and Firefox 3.5 or higher.

Google sees the new option as a response to sites that you may consider offensive, pornographic, or of low quality. It's also just the latest effort in the company's war against content farms. The search giant recently revamped its search algorithm to reward higher-quality sites and lower the rankings of those considered low quality. Google said it's not currently using the new blocked sites option to influence its search rankings but promises to review the data and see if it could prove useful down the road.