Takeshi Natsuno wants your wallet. Money, credit cards, driver's license, pictures of Junior and Sis-the works. And while he's at it, he'll take your keys, your bank passbook, and a bunch of your other valuable stuff. But Natsuno is no thief. He's the managing director for i-mode strategy at NTT DoCoMo, the biggest cell-phone company in Japan-and one of the most innovative telecommunications firms anywhere in the world. His title bears some explanation: "NTT" stands for Nippon Telegraph and Telephone, the former state telephone firm that owns two-thirds of his company. "DoCoMo" is a labored English acronym for "Do Communications over the Mobile Network," as well as a play on the Japanese word dokomo, which means "anywhere." And "i-mode" is DoCoMo's wireless Internet service-by far the world's most successful, with some 41 million subscribers in Japan alone (compared to four million for Sprint's PCS Vision, the first popular wireless data service in the United States), not to mention licensed versions in seven European nations and Taiwan. Natsuno wants your wallet because DoCoMo plans to build on i-mode to transform the cell phone into a kind of remote control for your entire life-and a preview of tomorrow's universal computing.

The plan will go into gear this summer, when DoCoMo introduces a new and radically more versatile type of phone. Like a regular cell phone, it will make and receive telephone calls. Like a regular i-mode device, it will let you send and receive e-mail, play online games, and access any one of the 78,000 i-mode-compatible websites around the world. And like other DoCoMo phones, it will take photographs, read bar codes, and play downloaded music over headphones or tiny but surprisingly good speakers. But it will also contain a special chip made by Sony that lets it pay for groceries, serve as personal identification, unlock doors, operate appliances, buy movie and subway tickets, and perform dozens of other tasks.