I love this Live Messenger Campaign highlighted by fellow User Experience Evangelist from the Netherlands, Martin Tirion. Built in Silverlight, it's a great example of one of the oldest user engagement tricks in the book: for a small action from the user, provide a big and dramatic response. I guess it's the most literal interpretation of 'empowering your users'.
It looks great and is quite compelling, even though I can't read Dutch, and I'm pulling it down all the way from Holland!
Great execution by RedUrban and Lightmaker.