The tech revolution at the nation's top law and business schools, where students now routinely use laptops and wireless connections in class, has created an insurgent population: professors, who believe they're losing the fight against wandering minds. In retaliation, at schools such as Harvard, Yale and Columbia, some profs have banned laptops from class altogether. In a more measured approach, the University of Chicago Law School cut its classroom Wi-Fi signal this spring, citing an "epidemic" of Web browsing during lectures, while at UCLA law, profs can activate a "kill switch" to disable Wi-Fi if they sense an attention deficit. The results, they say, are striking. "I'm getting much better eye contact," says Michigan law professor Richard Friedman, who installed a no-laptop policy in January. "It's been like renewing an acquaintance with an old friend." To others, though, the crackdown lets the real culprits off the hook. "If you're so boring that students are zoning out, you ought to rethink if you should be teaching," says UCLA law professor Stephen Bainbridge—though he admits that he's flipped the kill switch in his own classroom more than once. Tetris, anyone?