Bob Berman's strange universe: If ET talks back
February 2006: Let's get serious and consider the challenges of communicating with ETs.
Imagine this: We receive the first real message from extraterrestrials (ETs). We translate the communication, and it turns out to be a list of planets, along with a suggestion: "Send a rocketful of deuterium to the first planet on the list. Then cross it off, write your own world's name on the bottom, and send this to all the other planets. In just a month, you'll receive a trillion shipments of hydrogen."