Outgoing Federal Communi-cations Commission chair Michael Powell once told an audience at the International Consumer Electronics Show that TiVo was “God's machine.” He's right. Once you've had one, you can never go back to dumb TV, where you're stuck watching whatever is actually on at that moment.

Today you can buy similar devices for radio—sometimes called RiVos—including Griffin's Radio Shark and Neuros's MP3 Computer, that connect to your computer and record programs to your hard drive.