Like to see big numbers by your name? Want to help Google put together meaningful search keys for image data? Then hop along to Google's Image Labeller and give this game a try.

It works like this - you are paired with a random partner on the service. During a 90 second window, you are presented with an image and asked to provide a description of it. Your partner is shown the same image. Only when the two of you suggest the same tag for the image do you get some points and then progress onto the next image. You can pass at any time, providing your partner also wants to pass.

It's strangely addictive, but alas the images are very small - perhaps a later iteration will fix that problem, but have a look anyway and see what you think.