Google Image Labeler is a feature of Google Search will allow you to label images and help improve the quality of Google’s image search results, having fun at the same time.

You’ll receive more points for matches with more descriptive labels. For example, this image can be described by the labels: sky (50 points), bird (60 points), soaring (120 points), or frigate bird (150 points).

You’ll be randomly paired with a partner who’s online and using the feature. Over a two-minute period, you and your partner will:

• View the same set of images.
• Provide as many labels as possible to describe each image you see.
• Receive points when your label matches your partner’s label. The number of points will depend on how specific your label is.
• See more images until 2 minutes passes out.

Login to your google account, choose a nickname and accumulate points. Well, Google is not rewarding contributers at the moment. You may just try it out for fun sake