Google had a fun and addictive game back in 2006 named Google Image Labeler. It basically had you type what the image was and when you and your opponent matched, you moved on to the next image.
But some time in 2011, the game went offline.
Google actually promoted the game on their home page in 2007.
It was a nice way for Google to get people to tag images but I guess that data harvest is no longer needed. Here is a video of the game from back in 2007:
There is a thread at Google Web Search Help where users are pleading for Google to bring back the game. If you want the game back, join the thread, maybe you can resurrect something Google decided to kill.
Forum discussion at Google Web Search Help.