IBM is working with Citizen Watch in an effort to bring a wristwatch computer to market. The watchmaker and computer giant on Thursday unveiled the WatchPad, the first prototype to come out of their collaboration. IBM researchers have come out with prototypes on their own over the past year and a half. Besides telling time, the WatchPad comes with calendar-scheduling software, a pager-like application for sending and receiving short messages, and a Bluetooth chip for wireless communication with notebooks, handheld computers and cell phones. Citizen will work on ways to bring such products to market. No timetable has been set for a commercial release. The two companies will also work with research universities on other devices. A smart watch has been a technological dream since the days when Dick Tracy battled Pruneface in the Great Depression. Designers, however, have been challenged by the limited amount of real estate inside wristwatches for processors, memory and other components. Battery power has also been a constraint. IBM showed off the first Linux watch prototype in June 2000. But as one IBM researcher noted later, the first computer watch really ran only one application well and that was to tell time. Nonetheless, progress has been slow and steady. By tinkering with Linux, IBM has reduced the amount of memory required to run the OS. In turn, this has helped increase the battery life to six hours. IBM has predicted all-day battery life will appear in a year or so. In March, IBM showed off another prototype watch at the CeBit trade show that featured an organic light emitting diode (OLED) display, which consumes less energy than conventional displays. Hewlett-Packard is working on a similar effort with Swatch. In trials in Switzerland, wearers can pass through a train station turnstile while the watch charges their bank accounts for the cost of the ticket. Citizen worked on the design of the new prototype, as well as the display and input functions. IBM concentrated on hardware architecture and software. See the Linux Lounge for the latest GNU/Linux and open source headlines. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the Linux lounge forum Let the editors know what you think in the Mailroom. And read other letters.