Push Notifications on your Mac
from MacRumors.

Apple's Safari browser includes a feature that allows users to subscribe to "push" notifications from any website. Pushes show up as notification badges on the top right of your screen and can be used to be instantly notified when there are new MacRumors stories.

We also now support Firefox and Chrome, though those push notifications will not be delivered unless the browser is open.

To Subscribe or Unsubscribe

In order to subscribe, you need OS X Mavericks (10.9) or a supported browser. Push subscriptions are easy to opt-in to and easy to unsubscribe.

If you have any questions or problems, email support@macrumors.com.