I stumbled on a TED video from Luis von Ahn the other week, I urge you to view it if you haven’t already – you can see it embedded below.

What is so incredible about Luis, is that he has implemented not one but two incredible projects aimed at solving some of the web’s biggest problems whilst using the power of the crowd. Does it work? You bet it does.

His first company reCaptcha focused on digitising books, making knowledge more accessible to more people worldwide. You’ve probably already used it. It is the field in an online form where it asks you to type the characters shown in an image. It prevents software from automatically completing millions of forms; an important service for thousands of companies, including TicketMaster, Twitter and Facebook. The really clever part is that Luis and his team throw up two images to be decyphered in every reCaptcha form. One is required to authenticate the form whilst the other is a word from a book that has yet to be decyphered. Millions of books have now been digitised thanks to reCaptcha forms. Not surprisingly, Google bought his company in 2009.

His next project, Duolingo is even more ambitious. He wants to translate the web and that’s no easy task. In fact, if you’ve ever used Babblefish or Google Translate, you’ll know that translation software has a ways to go. A quick calculation also revealed that to do this through human translators would be more expensive than anyone could afford or would be willing to pay.

Could the crowd help? Well yes. Duolingo provides language courses for anyone, completely for free. However, the clever part is that as part of the learning experience, students will get to translate ‘live’ pages from the web. Not only does Luis not need to pay for these translations but learners are keen to do this work. A transparent crowdsourced review process ensures that the quality of each translation is high.

I’ve been using this tool on my PC and on my mobile for a few weeks now and from my experience it works brilliantly. Having achieved a base level of Spanish I’ve now started to translate my first web pages. Every translation I make helps my language skills. Brilliant. Hats off to you Luis.

Do you have similar examples of great crowdsourced projects you’d like to share?

Look forward to your comments.

Alan