At Serious Play 2008, astrophysicist George Smoot shows stunning new images from deep-space surveys, and prods us to ponder how the cosmos -- with its giant webs of dark matter and mysterious gaping voids -- got built this way.

"Rock-star physicist" Brian Cox talks about his work on the Large Hadron Collider at CERN. Discussing the biggest of big science in an engaging, accessible way, Cox brings us along on a tour of the massive project.

A pioneer in research on play, Dr. Stuart Brown says humor, games, roughhousing, flirtation and fantasy are more than just fun. Plenty of play in childhood makes for happy, smart adults -- and keeping it up can make us smarter at any age.