Those viral marketing campaigns are getting more and more creative. Skype, a free video-call service, schemed up a way to get people to engage with their product, pay a giggle forward, and put the laughter-is-contagious theory to the test. It's called the laughter chain. The chain begins with a baby giggling, then jumps to a dude LOLing while watching an online vid of the baby giggling then moves to an older man chuckling (the best chuckle ever!) while watching the dude LOL, and so on. Visit the Skype website for more details and throw yourself into the mix for the fun(ny) of it.