Professor Einstein rolls his eyes, sticks out his tongue, and can give a simple explanation of the theory of relativity. With his lifelike rubbery "skin" and bushy mustache, he can almost make you forget he's a robot. The Einstein robot is among dozens roaming the Consumer Electronics Show in Las Vegas that can be your companion, educator or babysit your children. While robots have been around for years, advances in technology and artificial intelligence have allowed developers to give them traits that enable the devices to be seen as members of the family. "We make robots that have personality and come to life," said Andy Rifkin, chief technology officer of Hanson Robotics, the Hong Kong-based firm which is bringing the $299 Einstein robot to consumers this year.