What does Google get by providing free games?

Ok, here is the latest addiction for all Google pros. Google has deployed this very interesting strategy for indexing its images so that Google users get better results. Check it out here:

http://images.google.com/imagelabeler/

You can log in as a Guest or sign in with your Google account. You will be paired with a randomly selected partner (any online Google users worldwide). Then, both you and the partner will see the same image and need to provide as many labels as possible for that image. The moment you and your partner provide a matching label, you get points for it and the next image is displayed. Needless to say, you cannot see the labels that your partner has provided until the allocated 2 minutes per round are over. Go ahead and give it a shot.

So what does Google get by providing free games? Well, with this fun, game experience, actually Google is getting the indexing done for all those images to appear in search results without paying a penny for the time and resources that all of us are spending!! Amazingly, Google comes up with such great ideas where they are actually getting a business project completed and its loyal users take it in the right spirit and enjoy the "games" while helping their own Google grow!