Google “I'm Feeling Lucky” button leads to mystery countdown clock

The feature, which generally takes users directly to the top result for their query, has been programmed to display a ticker when no words are entered into the search box.

As of 7.15pm GMT on Monday, the clock had reached 1,484,258.

Seemingly the blue numbers are only visible to people using the search giant's English language portals such as Google.com, Google.co.uk, Google.ie and Google.com.au. Attempting the same trick on Google's French and German sites gives an error box instead.

Google has not released any statement regarding the explanation of the hidden countdown, but initial speculation that the search engine giant had advance warning of the end of the world appears wide of the mark.

Simple calculations indicate that the number will reach 0 in 17 days – around the turn in the New Year.

If it is confirmed then this will be the latest in a long line of pranks and hidden treats dropped into Google products by the US firm's engineers.

Past "easter eggs", as they are known, include:

• Type "recursion" into the search box and it suggests "recursion" as an alternative, sending you on a loop of clicks that all generate identical results.

• With the arrow keys, type "up, up, down, down, left, right, left, right, B, A" while using the firm's RSS feed reader, and a little ninja appears on the left of the screen, which turns partially blue.

• The Mars feature of Google Earth 5 permits the user to explore the surface of the Red Planet and chat to the locals. Typing "Meliza" into the search box will takes you to an area of the planet where you can strike up a conversation with a Martian.