Worried you were being too productive today? Have no fear, the coders at Google have the perfect remedy.

In the popular real-time strategy genre of video games, the term "rush" is applied to any tactic in which you aim several of your battle units at your enemy at once, immediately overpowering them through sheer weight of numbers.

In the hugely successful real-time strategy game Star Craft, it's a common tactic used by the alien race known as the Zergs.

Google has crafted a rather amusing little Easter egg - just run a search for "Zerg rush" and see what happens.

As you'll immediately notice, little Os are now running around the screen attacking and destroying every search result – you even see the life bars depleting in true RTS style.

But you can also fight back. Clicking on each Zerg several times will defeat them, so take out as many as you can. When the animation finishes, you can post your score to Google+.

The good thing is when your bosses catches you playing, you can just claim your PC has been infected by a virus and spend the rest of the afternoon reading the newspaper while tech support investigates.